View source for Alameda County, California

{{Short description|County in California, United States}}
{{Use American English|date=June 2025}}
{{Use mdy dates|date=April 2024}}
{{Infobox settlement
<!--See the table at Template:Infobox settlement for all fields and descriptions of their usage.-->
 | name                     = Alameda County
 | settlement_type          = [[List of counties in California|County]]
| image_skyline      = {{multiple image
  | total_width        = 280
  | border             = infobox
  | perrow             = 1/2/2/1
  | caption_align      = center
  | image1             = Missionpeak (cropped).jpg
  | caption1           = [[Mission Peak]] in the [[Diablo Range]]
  | image2             = OAKLAND,_CA,_USA_-_Skyline_and_Bridge_(cropped).JPG
  | caption2           = [[Oakland]]
  | image3             = Livermore_Valley_Sunrise_-_Flickr_-_Jaykhuang.jpg 
  | caption3           = [[Livermore Valley]]
  | image4             = Alameda_Island_June_2023.jpg
  | caption4           = [[Alameda (island)|Alameda Island]]
  | image5             = Berkeley cityscape at sunrise (cropped).jpg
  | caption5           = [[Berkeley, California|Berkeley]]
  | image7             = View of the Alameda County Coast.jpg
  | caption7           = Alameda County coast on [[San Francisco Bay]]
  }}
 | image_flag               = Flag of Alameda County, California.svg
 | image_seal               = Seal of Alameda County, California.svg
 | image_map                = {{Maplink|frame=yes|plain=yes|frame-width=250|frame-align=center|type=shape-inverse|stroke-color=#808080|fill=#808080|fill-opacity=0.4|zoom=8}}
 | map_caption              = Interactive map of Alameda County
 | image_map1               = Map of California highlighting Alameda County.svg
 | mapsize1                 = 200px
 | map_caption1             = Location in California
 | coordinates = {{Coord|37.65|-121.91|display=title,inline|type:adm2nd_region:US-CA_source:UScensus1990}}
 | subdivision_type         = [[List of sovereign states|Country]]
 | subdivision_name         = {{Flagu|United States}}
 | subdivision_type1        = [[U.S. state|State]]
 | subdivision_name1        = {{Flag|California}}
 | subdivision_type2  = [[Regions of California|Region]]
 | subdivision_name2  = [[San Francisco Bay Area|Bay Area]]
 | established_title        = [[Municipal corporation|Incorporated]]
 | established_date         = March 25, 1853<ref>{{Cite GNIS|1675839|Alameda County|access-date=January 22, 2015}}</ref>
 | named_for                = [[Rancho Arroyo de la Alameda]] (also see [[Alameda Creek]])
 | seat_type                = [[County seat]]
 | seat                     = [[Oakland, California|Oakland]]
 | parts_type               = Largest city
 | parts                    = Oakland (population)<br />[[Fremont, California|Fremont]] (area)
<!-- Government ----------->
 | government_type          = [[Council–manager government|Council–CAO]]
 | governing_body           = [[Alameda County Board of Supervisors]]
 | leader_title1            = President
 | leader_name1             = David Haubert
 | leader_title2            = Vice President
 | leader_name2             = Lena Tam
 | leader_title3            = Board of Supervisors<ref>{{Cite web|url=https://bos.acgov.org/|title=Home &#124; Board of Supervisors &#124; Alameda County|website=bos.acgov.org}}</ref>
 | leader_name3             = {{Collapsible list
| title = Supervisors
| frame_style = border:none; padding:0;
| list_style  = text-align:left;
| 1  = David Haubert
| 2  = Elisa Márquez
| 3  = Lena Tam
| 4  = Nate Miley
| 5  = Nikki Fortunato Bas
}}
 | leader_title4            = County Administrator's Office
 | leader_name4             = Susan S. Muranishi
 | unit_pref                = US
 | area_total_sq_mi         = 821
 | area_land_sq_mi          = 739
 | area_water_sq_mi         = 82
<!-- Elevation ------------>
 | elevation_min_ft         = 
<!-- Population ----------->
 | elevation_max_footnotes  = <ref>{{cite web|url=http://www.peakbagger.com/peak.aspx?pid=1213|title=Discovery Peak|publisher=Peakbagger.com|access-date=March 15, 2015}}</ref>
 | elevation_min_footnotes  = 
 | population_as_of         = 2020
 | population_total         = 1,682,353
 | pop_est_as_of            = 2024
 | population_est           = 1,649,060 {{loss}}
 | population_density_sq_mi = auto
 | population_footnotes     = <ref name="2020quickfacts" />
 | pop_est_footnotes        = 
<!-- GDP ----------->
| demographics_type2       = GDP
| demographics2_footnotes  = <ref name="bea.gov">{{cite web |url = https://fred.stlouisfed.org/series/GDPALL06001 |title = Gross Domestic Product: All Industries in Alameda County, CA |website = fred.stlouisfed.org}}</ref>
|demographics2_title1     = Total
|demographics2_info1      = $168.506 billion (2022) 
 | postal_code_type         = <!--[[ZIP code]]s-->
 | postal_code              = 
 | area_code                = [[Area codes 510 and 341|510, 341]], [[Area code 925|925]]
 | area_code_type           = [[North American Numbering Plan|Area codes]]
 | elevation_max_ft         = 3843
 | timezone                 = [[Pacific Time Zone]]
 | utc_offset               = −8
 | timezone_DST             = [[Pacific Daylight Time]]
 | utc_offset_DST           = −7
 | blank_name_sec2          = Congressional districts
 | blank_info_sec2          = [[California's 10th congressional district|10th]], [[California's 12th congressional district|12th]], [[California's 14th congressional district|14th]], [[California's 17th congressional district|17th]]
 | blank_name_sec1          = [[Federal Information Processing Standard|FIPS]] code
 | blank_info_sec1          = 06-001
 | blank1_name_sec1         = [[Geographic Names Information System|GNIS]] feature ID
 | website                  = {{URL|www.acgov.org|ACgov.org}}
}}

'''Alameda County''' ({{IPAc-en|audio=En-us-alameda.ogg|ˌ|æ|l|ə|'|m|i:|d|ə}} {{respell|AL|ə|MEE|də}}) is a [[List of counties in California|county]] located in the U.S. state of [[California]]. As of the [[2020 United States census|2020 census]], the population was 1,682,353,<ref name="2020quickfacts">{{cite web|date=2020|title=U.S. Census Bureau QuickFacts: Alameda County, California|url=https://www.census.gov/quickfacts/fact/table/alamedacountycalifornia/POP010220|access-date=September 20, 2021|website=[[United States Census Bureau]]}}</ref><ref>{{cite web|title=Alameda County, California|url=https://data.census.gov/cedsci/profile?g=0500000US06001|website=[[United States Census Bureau]]|accessdate=January 30, 2022}}</ref> making it the 7th-most populous county in the state<ref>[http://www.alameda.courts.ca.gov/pages.aspx/about-alameda-county About Alameda County – County of Alameda – Superior Court of California] {{Webarchive|url=https://web.archive.org/web/20180618125619/http://www.alameda.courts.ca.gov/pages.aspx/about-alameda-county |date=June 18, 2018 }} Alameda.courts.ca.gov. Retrieved on July 15, 2013.</ref> and [[List of the most populous counties in the United States|21st]] most populous nationally. The [[county seat]] is [[Oakland, California|Oakland]].<ref name="GR6">{{cite web|url=http://www.naco.org/Counties/Pages/FindACounty.aspx |access-date=June 7, 2011 |title=Find a County |publisher=National Association of Counties |url-status=dead |archive-url=https://web.archive.org/web/20110531210815/http://www.naco.org/Counties/Pages/FindACounty.aspx |archive-date=May 31, 2011 }}</ref> Alameda County is in the [[San Francisco Bay Area]], occupying much of the [[East Bay (San Francisco Bay Area)|East Bay]] region.

The [[Spanish language|Spanish]] word ''alameda'' means either "a grove of poplars...or a tree lined street".  The name was originally used to describe the [[Alameda Creek|Arroyo de la Alameda]]; the [[willow]] and [[sycamore]] trees along the banks of the river reminded the early Spanish explorers of a road lined with trees.<ref>{{Cite web|url=https://www.lexico.com/en/definition/alameda|archive-url=https://web.archive.org/web/20191026205612/https://www.lexico.com/en/definition/alameda|url-status=dead|archive-date=October 26, 2019|title=ALAMEDA English Definition and Meaning |website=Lexico Dictionaries &#124; English}}</ref><ref>{{Cite web|url=https://www.merriam-webster.com/dictionary/alameda|title=Definition of ALAMEDA|website=Merriam-Webster }}</ref>

Alameda County is part of the [[San Francisco–Oakland–Berkeley, CA Metropolitan Statistical Area]], and the [[San Jose–San Francisco–Oakland, CA Combined Statistical Area]].

== History ==
The county was formed on March 25, 1853, from a large portion of [[Contra Costa County, California|Contra Costa County]] and a smaller portion of [[Santa Clara County, California|Santa Clara County]].

The county seat at the time of the county's formation was located at [[Alvarado, California|Alvarado]], now part of [[Union City, California|Union City]]. In 1856, it was moved to [[San Leandro, California|San Leandro]], where the county courthouse was destroyed by the devastating 1868 quake on the [[Hayward Fault]]. The county seat was then re-established in the town of [[Brooklyn, California|Brooklyn]] from 1872 to 1875. Brooklyn is now part of [[Oakland, California|Oakland]], which has been the county seat since 1873.

Much of what is now an intensively [[urban area|urban]] region was initially developed as a [[trolley car suburb]] of [[San Francisco, California|San Francisco]] in the late 19th and early 20th centuries. The [[Key System]] moved commuters to and from the [[Key System Mole]], where [[Ferries of San Francisco Bay|ferries bridged the gap]] across [[San Francisco Bay]].

The historical progression from Native American tribal lands to Spanish then Mexican ranches, then to farms, ranches, and orchards, then to multiple city centers and suburbs, is shared with the adjacent and closely associated [[History of Contra Costa County, California|Contra Costa County]].

==Law, government and politics==
[[File:Oakland Court House California USA2.jpg|thumb|[[René C. Davidson Courthouse]], [[Alameda County Superior Court]], Oakland, in June 2009]]

===Government===
{{Main|Government of Alameda County, California}}

The [[Government of Alameda County, California|Government of Alameda County]] is defined and authorized under the [[California Constitution]], [[California law]], and the Charter of the County of Alameda.<ref>California Government Code § 23004</ref> Much of the [[Government of California]] is in practice the responsibility of county governments such as the Government of Alameda County, while municipalities such as the City of [[Oakland, California|Oakland]] and the City of [[Berkeley, California|Berkeley]] provide additional, often non-essential services. The County government provides countywide services such as elections and voter registration, law enforcement, jails, vital records, property records, tax collection, and public health. In addition it is the local government for all unincorporated areas, and provides services such as law enforcement to some incorporated cities under a contract arrangement.

It is composed of the elected five-member [[Alameda County Board of Supervisors]] (BOS) as the county legislature, several other elected offices and officers including the [[Alameda County Sheriff's Department|Sheriff]], the [[Alameda County District Attorney|District Attorney]], [[Alameda County Assessor|Assessor]], [[Alameda County Auditor-Controller/County Clerk/Recorder|Auditor-Controller/County Clerk/Recorder]], [[Alameda County Treasurer/Tax Collector|Treasurer/Tax Collector]], and numerous county departments and entities under the supervision of the County Administrator. In addition, several entities of the [[government of California]] have jurisdiction conterminous with Alameda County, such as the [[Alameda County Superior Court]].

The current supervisors are:<ref>{{cite web|url=http://www.acgov.org/board/|title=Board of Supervisors|publisher=Alameda County|access-date=January 22, 2015}}</ref>
* David Haubert, district 1,
* Elisa Márquez, district 2,
* Lena Tam, district 3,
* Nate Miley, district 4, and
* Keith Carson, district 5.

The Board elects a president who presides at all meetings of the Board and appoints committees to handle work involving the major programs of the county. If the president is absent for a meeting, the vice president shall be responsible. A Board election occurs every two years for these positions. Supervisor Carson is serving currently as president; Supervisor Miley is vice president.

The county's law enforcement is overseen by an elected Sheriff/Coroner and an elected District Attorney. The Sheriff supervises the deputies of the [[Alameda County Sheriff's Office]], whose primary responsibilities include policing unincorporated areas of the county and cities within the county which contract with the Sheriff's Office for police services; providing security and law enforcement for county buildings including courthouses, the county jail and other county properties; providing support resources, such as a forensics laboratory and search and rescue capabilities, to other law enforcement agencies throughout the county; and serving the process of the county's Superior Court system. The District Attorney's office is responsible for prosecuting all criminal violations of the laws of the state of California, the county, or its constituent municipalities, in the Alameda County Superior Court. The current Sheriff is [[Yesenia Sanchez]], who was elected in 2022, succeeding [[Greg Ahern]], who had served in the post for 16 years. The Sheriff's Office operates two jails: [[Santa Rita Jail]] in [[Dublin, CA|Dublin]], and [[Glenn E. Dyer Detention Facility]] in downtown [[Oakland, CA|Oakland]].

In 2009, [[Nancy E. O'Malley]] was appointed Alameda County district attorney after [[Tom Orloff]] retired. She served two terms and did not run for reelection in 2022.<ref>{{cite news |last1=Morris |first1=Scott |title=Alameda County District Attorney Nancy O'Malley is stepping aside |url=https://oaklandside.org/2021/07/15/alameda-county-district-attorney-nancy-omalley-legacy-victims-rights-police-accountability/ |access-date=July 28, 2022 |work=The Oaklandside |date=July 15, 2021}}</ref> [[Pamela Price]] was elected as district attorney in 2022.<ref>{{Cite web |last=Sharpe |first=Joshua |date=November 19, 2022 |title=Civil rights attorney Pamela Price makes history as Alameda County's next district attorney |url=https://www.sfchronicle.com/election/article/Civil-rights-attorney-Pamela-Price-makes-history-17596670.php |access-date=September 17, 2023 |website=San Francisco Chronicle |language=en-US}}</ref>

The Alameda County Fire Department (ACFD)<ref>{{Cite web|url=http://www.acgov.org/fire/|title=Alameda County Fire Department|access-date=June 22, 2010|archive-date=March 29, 2016|archive-url=https://web.archive.org/web/20160329195026/http://acgov.org/fire/|url-status=dead}}</ref> was formed on July 1, 1993, as a dependent district, with the Board of Supervisors as its governing body. Municipal and specialized fire departments have been consolidated into the ACFD over the years. 1993 brought in the Castro Valley and Eden Consolidated FD, and the County Fire Patrol. San Leandro joined in 1995, Dublin in 1997, [[Lawrence Berkeley National Laboratory]] in 2002, [[Lawrence Livermore National Laboratory]] in 2007, The [[Alameda County Regional Emergency Communications Center]] in 2008, and Newark and Union City in 2010. Emeryville joined the ACFD in 2012.

The [[Alameda County Water District]] is a special district within Alameda County created to distribute water, but it is not operated by Alameda County administrators. It is operated by an elected board of directors.

[[Alameda County Superior Court]] operates in twelve separate locations throughout the county, with its central [[René C. Davidson Courthouse]] located in Oakland near [[Lake Merritt]]. Most major criminal trials and complex civil cases are heard at this location or in courtrooms within the County Administration Building across the street.

===State and federal representation===

In the [[California State Assembly]], Alameda County is split between five districts:
* {{Representative|caad|14|fmt=adistrict}}
* {{Representative|caad|16|fmt=adistrict}}
* {{Representative|caad|18|fmt=adistrict}}
* {{Representative|caad|20|fmt=adistrict}}
* {{Representative|caad|24|fmt=adistrict}}<ref>{{cite web
 |url=https://www.assembly.ca.gov/assemblymembers
 |title=Members Assembly
 |access-date=November 4, 2025
|publisher=State of California}}</ref>

In the [[California State Senate]], the county is split between four districts:
* {{Representative|casd|5|fmt=sdistrict}}
* {{Representative|casd|7|fmt=sdistrict}}
* {{Representative|casd|9|fmt=sdistrict}}
* {{Representative|casd|10|fmt=sdistrict}}<ref>{{cite web
 |url=https://www.senate.ca.gov/senators
 |title=Senators
 |access-date=November 4, 2025
|publisher=State of California}}</ref>

In the [[United States House of Representatives]], the county is split between four districts:
* {{Representative|cacd|10|fmt=district}}
* {{Representative|cacd|12|fmt=district}}
* {{Representative|cacd|14|fmt=district}} 
* {{Representative|cacd|17|fmt=district}}

===Politics===
Since 1932, Alameda County has been a stronghold of the Democratic Party, with [[Dwight Eisenhower]] being the only Republican presidential nominee to have carried the county since. Prior to 1932, the county had been a Republican stronghold. [[Piedmont, California|Piedmont]] resident [[William F. Knowland]] was the Republican U.S. Senate Leader from 1953 to 1959. Even when [[Ronald Reagan]] won the national popular vote by an 18.3% margin in [[1984 United States presidential election|1984]], [[Walter Mondale]] won Alameda County by a larger margin. In [[2004 United States presidential election|2004]] it voted for [[John Kerry]], who won over 75% of the vote. Every city and town voted Democratic.<ref>[https://web.archive.org/web/20050428183315/http://www.ss.ca.gov/elections/sov/2004_general/ssov/pres_general_ssov_all.pdf pres_general_ssov_for_all.xls<!-- Bot generated title -->]</ref> George H.W. Bush in 1988 was the last Republican to break 30% of the county's vote and Ronald Reagan in 1984 was the last to break 40% of the vote (carrying 40.01%).<ref name="Leip">{{cite web|url=http://uselectionatlas.org/RESULTS/index.html|title=Dave Leip's Atlas of U.S. Presidential Elections|last=Leip|first=David|website=uselectionatlas.org|access-date=August 30, 2018}}</ref>

{{PresHead|place=Alameda County, California|source=<ref name="Leip"/>}}
<!-- PresRow should be {{PresRow|Year|Winning party|GOP vote #|Dem vote #|3rd party vote #|State}} -->
{{PresRow|2024|Democratic|140,789|499,551|29,567|California}}
{{PresRow|2020|Democratic|136,309|617,659|19,785|California}}
{{PresRow|2016|Democratic|95,922|514,842|48,779|California}}
{{PresRow|2012|Democratic|108,182|469,684|19,027|California}}
{{PresRow|2008|Democratic|119,555|489,106|14,252|California}}
{{PresRow|2004|Democratic|130,911|422,585|8,594|California}}
{{PresRow|2000|Democratic|119,279|342,889|32,168|California}}
{{PresRow|1996|Democratic|106,581|303,903|51,560|California}}
{{PresRow|1992|Democratic|109,292|334,224|86,629|California}}
{{PresRow|1988|Democratic|162,815|310,283|5,899|California}}
{{PresRow|1984|Democratic|192,408|282,041|6,425|California}}
{{PresRow|1980|Democratic|158,531|201,720|57,366|California}}
{{PresRow|1976|Democratic|155,280|235,988|16,413|California}}
{{PresRow|1972|Democratic|201,862|259,254|10,079|California}}
{{PresRow|1968|Democratic|153,285|219,545|34,519|California}}
{{PresRow|1964|Democratic|142,998|283,833|509|California}}
{{PresRow|1960|Democratic|183,354|217,172|1,474|California}}
{{PresRow|1956|Republican|192,911|174,033|1,187|California}}
{{PresRow|1952|Republican|201,976|178,239|3,079|California}}
{{PresRow|1948|Democratic|150,588|154,549|18,194|California}}
{{PresRow|1944|Democratic|122,982|169,631|1,374|California}}
{{PresRow|1940|Democratic|116,961|148,224|3,311|California}}
{{PresRow|1936|Democratic|82,352|149,323|3,011|California}}
{{PresRow|1932|Democratic|89,303|106,388|8,761|California}}
{{PresRow|1928|Republican|118,539|60,875|1,780|California}}
{{PresRow|1924|Republican|81,454|8,020|43,016|California}} 
{{PresRow|1920|Republican|73,177|21,468|11,244|California}}
{{PresRow|1916|Republican|51,417|43,748|6,966|California}}
{{PresRow|1912|Progressive|0|24,418|42,034|California}}
{{PresRow|1908|Republican|21,380|7,110|4,793|California}} 
{{PresRow|1904|Republican|19,065|4,399|3,646|California}}
{{PresRow|1900|Republican|14,324|6,677|1,158|California}}
{{PresRow|1896|Republican|13,429|8,394|400|California}}
{{PresRow|1892|Republican|8,792|7,114|2,564|California}}
{{PresRow|1888|Republican|8,840|5,693|928|California}}
{{PresRow|1884|Republican|7,471|4,734|193|California}}
{{PresFoot|1880|Republican|5,899|3,894|96|California}}

On November 4, 2008, Alameda County voted 61.92% against [[California Proposition 8 (2008)|Proposition 8]], which won statewide, and which amended the [[California Constitution]] to ban [[same-sex marriage]]. The county garnered the sixth highest "no" vote, by percentage, of all California counties, and was the second largest county, by total voter turnout, to vote against it.<ref>{{cite web |url=http://www.sos.ca.gov/elections/sov/2008_general/sov_complete.pdf |title= Statement of Vote |website=www.sos.ca.gov |archive-url=https://web.archive.org/web/20121018225250/http://www.sos.ca.gov/elections/sov/2008_general/sov_complete.pdf |archive-date=October 18, 2012}}</ref>

==== Voter registration statistics as of October 24, 2022====

{| class="wikitable collapsible collapsed"
|-
! colspan="3" | Population and registered voters
|-
! scope="row" style="text-align: left;" | Total eligible population<ref name="2022reg">{{cite web |title=Statement of Vote, November 8, 2022, General Election |url=https://elections.cdn.sos.ca.gov/sov/2022-general/sov/complete.pdf |website=California Secretary of State |access-date=May 5, 2023}}</ref>
| colspan="2" | 1,140,774
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Registered voters<ref name="2022reg"/><ref name="PCT-RV" group=note>Percentage of registered voters with respect to total population. Percentages of party members with respect to registered voters follow.</ref>
| 931,130
| 81.6%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;Democratic<ref name="2022reg"/>
| 562,093
| 60.4%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;Republican<ref name="2022reg"/>
| 100,977
| 10.8%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;Democratic–Republican spread<ref name="2022reg"/>
| <span style="color:#00f;">'''+461,116'''</span>
| <span style="color:#00f;">'''+49.6%'''</span>
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;American Independent<ref name="2022reg"/>
| 21,621
| 2.3%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;Libertarian<ref name="2022reg"/>
| 6,351
| 0.6%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;Green<ref name="2022reg"/>
| 5,628
| 0.6%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;Peace and Freedom<ref name="2022reg"/>
| 4,340
| 0.4%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;Unknown<ref name="2022reg"/>
| 26
| 0.0%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;Other<ref name="2022reg"/>
| 5,686
| 0.6%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;&nbsp;&nbsp;No party preference<ref name="2022reg"/>
| 224,408
| 24.1%
|}

===== Cities by population and voter registration =====

{| class="wikitable collapsible collapsed sortable" style="width: 100%;"
|-
! colspan="8" | Cities by population and voter registration as of 2013
|-
! City
! data-sort-type="number" | Population<ref name="US-CB-B02001"/>
! data-sort-type="number" | Registered voters<ref name="CA-SS">California Secretary of State. [http://www.sos.ca.gov/elections/ror/ror-pages/ror-odd-year-2013/political-sub.pdf February 10, 2013 – Report of Registration] {{webarchive|url=https://web.archive.org/web/20130727173649/http://www.sos.ca.gov/elections/ror/ror-pages/ror-odd-year-2013/political-sub.pdf |date=July 27, 2013 }}. Retrieved October 31, 2013.</ref><br /><ref name="PCT-RV" group=note/>
! data-sort-type="number" | Democratic<ref name="CA-SS"/>
! data-sort-type="number" | Republican<ref name="CA-SS"/>
! data-sort-type="number" | D–R spread<ref name="CA-SS"/>
! data-sort-type="number" | Other<ref name="CA-SS"/>
! data-sort-type="number" | No party preference<ref name="CA-SS"/>
|-
| [[Alameda, California|Alameda]] || 73,239 || 59.7% || 55.0% || 14.2% || <span style="color:#00f;">'''+40.8%'''</span> || 10.0% || 20.8%
|-
| [[Albany, California|Albany]] || 18,217 || 59.1% || 64.0% || 6.5% || <span style="color:#00f;">'''+57.5%'''</span> || 11.8% || 18.9%
|-
| [[Berkeley, California|Berkeley]] || 111,008 || 72.9% || 64.7% || 4.4% || <span style="color:#00f;">'''+60.3%'''</span> || 15.3% || 17.0%
|-
| [[Dublin, California|Dublin]] || 44,171 || 52.7% || 42.7% || 24.6% || <span style="color: #2b00d6;">'''+18.1%'''</span> || 14.3% || 21.3%
|-
| [[Emeryville, California|Emeryville]] || 9,698 || 64.7% || 59.6% || 7.6% || <span style="color:#00f;">'''+52.0%'''</span> || 15.3% || 19.5%
|-
| [[Fremont, California|Fremont]] || 211,748 || 47.9% || 46.4% || 17.5% || <span style="color:#00f;">'''+28.9%'''</span> || 12.2% || 26.0%
|-
| [[Hayward, California|Hayward]] || 142,936 || 43.7% || 60.1% || 12.7% || <span style="color:#00f;">'''+47.4%'''</span> || 11.0% || 18.4%
|-
| [[Livermore, California|Livermore]] || 79,710 || 61.5% || 39.4% || 33.1% || <span style="color:purple;">'''+6.3%'''</span> || 12.4% || 18.2%
|-
| [[Newark, California|Newark]] || 42,322 || 48.6% || 53.9% || 16.6% || <span style="color:#00f;">'''+37.3%'''</span> || 10.7% || 21.1%
|-
| [[Oakland, California|Oakland]] || 389,397 || 55.4% || 66.7% || 5.9% || <span style="color:#00f;">'''+60.8%'''</span> || 12.1% || 16.9%
|-
| [[Piedmont, California|Piedmont]] || 10,640 || 79.7% || 56.0% || 19.6% || <span style="color:#00f;">'''+36.4%'''</span> || 8.4% || 17.9%
|-
| [[Pleasanton, California|Pleasanton]] || 69,220 || 61.5% || 38.2% || 31.8% || <span style="color:purple;">'''+6.4%'''</span> || 12.0% || 20.5%
|-
| [[San Leandro, California|San Leandro]] || 83,877 || 50.9% || 58.7% || 13.7% || <span style="color:#00f;">'''+45.0%'''</span> || 10.2% || 19.5%
|-
| [[Union City, California|Union City]] || 68,830 || 48.6% || 54.9% || 13.1% || <span style="color:#00f;">'''+41.8%'''</span> || 10.5% || 23.3%
|}

==Geography and climate==
[[File:Oaklandatnight02192006.JPG|thumb|View of [[downtown Oakland]] looking west across [[Lake Merritt]]]]
[[File:BerkeleyAndBayAtNight.jpg|thumb|View of Berkeley and the San Francisco Bay at nightfall]]
[[File:Mission-SJ.jpg|thumb|175px|The reconstructed mission at [[Mission San José (California)|Mission San José]] (located in Fremont)]]

According to the [[U.S. Census Bureau]], the county has a total area of {{convert|821|sqmi}}, of which {{convert|739|sqmi}} is land and {{convert|82|sqmi}} (10%) is water.<ref name="GR1">{{cite web|url=http://www2.census.gov/geo/docs/maps-data/data/gazetteer/counties_list_06.txt|publisher=United States Census Bureau|access-date=September 24, 2015|date=August 22, 2012|title=2010 Census Gazetteer Files}}</ref> The [[San Francisco Bay]] borders the county on the west.

The crest of the [[Berkeley Hills]] forms part of the northeastern boundary and reaches into the center of the county. A coastal plain several miles wide lines the bay; and is Oakland's most populous region. Livermore Valley lies in the eastern part of the county. Amador Valley abuts the western edge of Livermore Valley and continues west to the Pleasanton Ridge. The ridges and valleys of the [[Diablo Range]], containing the county's highest peaks, cover the very sparsely populated southeast portion of the county.

The [[Hayward Fault]], a major branch of the San Andreas Fault to the west, runs through the most populated parts of Alameda County, while the [[Calaveras Fault]] runs through the southeastern part of the county.

The areas near the Bay itself have a maritime [[warm-summer Mediterranean climate]], whereas behind the mountains, summers are significantly warmer. The climate charts below are for [[Oakland, California|Oakland]] and inland [[Livermore, California|Livermore]].

{{Weather box
|location = Oakland Museum (1981–2010 normals, extremes 1970–present)
|single line = Y
|width = auto
| Jan record high F  = 78
| Feb record high F  = 82
| Mar record high F  = 88
| Apr record high F  = 97
| May record high F  = 105
| Jun record high F  = 106
| Jul record high F  = 103
| Aug record high F  = 99
| Sep record high F  = 109
| Oct record high F  = 103
| Nov record high F  = 84
| Dec record high F  = 75
| year record high F = 109
| Jan avg record high F  = 67.0
| Feb avg record high F  = 72.4
| Mar avg record high F  = 75.9
| Apr avg record high F  = 82.8
| May avg record high F  = 85.5
| Jun avg record high F  = 89.1
| Jul avg record high F  = 87.3
| Aug avg record high F  = 88.7
| Sep avg record high F  = 89.7
| Oct avg record high F  = 87.8
| Nov avg record high F  = 75.8
| Dec avg record high F  = 66.5
| year avg record high F = 94.7
| Jan high F  = 58.0
| Feb high F  = 61.8
| Mar high F  = 63.6
| Apr high F  = 66.0
| May high F  = 68.8
| Jun high F  = 71.2
| Jul high F  = 71.7
| Aug high F  = 73.0
| Sep high F  = 74.1
| Oct high F  = 71.7
| Nov high F  = 64.6
| Dec high F  = 58.1
| year high F = 66.6
| Jan mean F  = 51.4
| Feb mean F  = 54.7
| Mar mean F  = 56.4
| Apr mean F  = 58.3
| May mean F  = 61.1
| Jun mean F  = 63.5
| Jul mean F  = 64.3
| Aug mean F  = 65.6
| Sep mean F  = 66.0
| Oct mean F  = 63.3
| Nov mean F  = 57.1
| Dec mean F  = 51.8
| year mean F = 59.2
| Jan low F  = 44.7
| Feb low F  = 47.7
| Mar low F  = 49.1
| Apr low F  = 50.5
| May low F  = 53.5
| Jun low F  = 55.7
| Jul low F  = 56.9
| Aug low F  = 58.1
| Sep low F  = 57.8
| Oct low F  = 55.1
| Nov low F  = 49.8
| Dec low F  = 45.4
| year low F = 51.9
| Jan avg record low F  = 38.0
| Feb avg record low F  = 40.0
| Mar avg record low F  = 42.2
| Apr avg record low F  = 45.2
| May avg record low F  = 49.1
| Jun avg record low F  = 51.9
| Jul avg record low F  = 54.0
| Aug avg record low F  = 55.5
| Sep avg record low F  = 53.8
| Oct avg record low F  = 49.0
| Nov avg record low F  = 41.6
| Dec avg record low F  = 37.3
| year avg record low F = 36.0
| Jan record low F  = 30
| Feb record low F  = 29
| Mar record low F  = 34
| Apr record low F  = 37
| May record low F  = 43
| Jun record low F  = 48
| Jul record low F  = 51
| Aug record low F  = 50
| Sep record low F  = 48
| Oct record low F  = 43
| Nov record low F  = 36
| Dec record low F  = 26
| year record low F = 26
| precipitation colour    = green
| Jan precipitation inch  = 4.59
| Feb precipitation inch  = 4.65
| Mar precipitation inch  = 3.52
| Apr precipitation inch  = 1.32
| May precipitation inch  = 0.73
| Jun precipitation inch  = 0.12
| Jul precipitation inch  = 0.00
| Aug precipitation inch  = 0.07
| Sep precipitation inch  = 0.23
| Oct precipitation inch  = 1.29
| Nov precipitation inch  = 3.07
| Dec precipitation inch  = 4.44
| year precipitation inch = 24.09
| unit precipitation days = 0.01 in.
| Jan precipitation days  = 10.2
| Feb precipitation days  = 10.5
| Mar precipitation days  = 10.7
| Apr precipitation days  = 5.9
| May precipitation days  = 3.4
| Jun precipitation days  = 1.0
| Jul precipitation days  = 0.1
| Aug precipitation days  = 0.4
| Sep precipitation days  = 1.2
| Oct precipitation days  = 3.5
| Nov precipitation days  = 8.1
| Dec precipitation days  = 10.4
| year precipitation days = 69.1
|source 1 = NOAA<ref name= NCDC >{{cite web|url = https://w2.weather.gov/climate/xmacis.php?wfo=mtr|title = NowData – NOAA Online Weather Data|publisher = [[National Oceanic and Atmospheric Administration]]|access-date = September 29, 2015}}</ref><ref name=NOAAtxt>{{cite web|url = ftp://ftp.ncdc.noaa.gov/pub/data/normals/1981-2010/products/station/USC00046336.normals.txt|title = CA Oakland Museum|publisher = [[National Oceanic and Atmospheric Administration]]|archive-url = https://web.archive.org/web/20170524230213/ftp://ftp.ncdc.noaa.gov/pub/data/normals/1981-2010/products/station/USC00046336.normals.txt|archive-date = 2017-05-24|url-status = dead|access-date = September 29, 2015}}</ref>
}}

{{Weather box
|collapsed = Y
|location = Livermore, California (1903–2013)
|single line = Y
|width = auto
|Jan record high F = 77
|Feb record high F = 80
|Mar record high F = 88
|Apr record high F = 96
|May record high F = 108
|Jun record high F = 113
|Jul record high F = 113
|Aug record high F = 112
|Sep record high F = 115
|Oct record high F = 106
|Nov record high F = 93
|Dec record high F = 79
|year record high F= 113
|Jan high F = 56.8
|Feb high F = 61.2
|Mar high F = 65.2
|Apr high F = 70.5
|May high F = 76.4
|Jun high F = 83.1
|Jul high F = 89.0
|Aug high F = 88.2
|Sep high F = 86.0
|Oct high F = 77.7
|Nov high F = 66.3
|Dec high F = 57.5
|year high F = 73.2
|Jan low F = 36.7
|Feb low F = 39.4
|Mar low F = 41.3
|Apr low F = 43.6
|May low F = 47.6
|Jun low F = 51.7
|Jul low F = 54.2
|Aug low F = 54.0
|Sep low F = 52.5
|Oct low F = 47.7
|Nov low F = 41.1
|Dec low F = 37.0
|year low F = 45.6
|Jan avg record high F=66.9
|Feb avg record high F=71.4
|Mar avg record high F=77.9
|Apr avg record high F=85.8
|May avg record high F=94.3
|Jun avg record high F=102.0
|Jul avg record high F=104.3
|Aug avg record high F=102.8
|Sep avg record high F=101.2
|Oct avg record high F=92.6
|Nov avg record high F=79.0
|Dec avg record high F=67.8
|year avg record high F=106.3
|Jan avg record low F=26.4 
|Feb avg record low F=29.5
|Mar avg record low F=32.1
|Apr avg record low F=34.9
|May avg record low F=39.3
|Jun avg record low F=44.4
|Jul avg record low F=47.7
|Aug avg record low F=47.8
|Sep avg record low F=44.5
|Oct avg record low F=38.3
|Nov avg record low F=30.5
|Dec avg record low F=26.7
|year avg record low F=24.5
|Jan record low F = 18
|Feb record low F = 21
|Mar record low F = 22
|Apr record low F = 29
|May record low F = 32
|Jun record low F = 38
|Jul record low F = 36
|Aug record low F = 36
|Sep record low F = 35
|Oct record low F = 29
|Nov record low F = 22
|Dec record low F = 18
|year record low F= 18
|Jan precipitation inch = 2.97
|Feb precipitation inch = 2.47
|Mar precipitation inch = 2.15
|Apr precipitation inch = 1.00
|May precipitation inch = .44
|Jun precipitation inch = .11
|Jul precipitation inch = .02
|Aug precipitation inch = .04
|Sep precipitation inch = .22
|Oct precipitation inch = .67
|Nov precipitation inch = 1.54
|Dec precipitation inch = 2.56
|unit precipitation days = .01 in
|Jan precipitation days = 10
|Feb precipitation days = 9
|Mar precipitation days = 9
|Apr precipitation days = 6
|May precipitation days = 3
|Jun precipitation days = 1
|Jul precipitation days = 0
|Aug precipitation days = 0
|Sep precipitation days = 1
|Oct precipitation days = 3
|Nov precipitation days = 7
|Dec precipitation days = 9
|year rain days = 58
| Jan snow days  =trace
| Feb snow days  =0.0
| Mar snow days  =0.0
| Apr snow days  =0.0
| May snow days  =0.0
| Jun snow days  =0.0
| Jul snow days  =0.0
| Aug snow days  =0.0
| Sep snow days  =0.0
| Oct snow days  =0.0
| Nov snow days  =0.0
| Dec snow days  =0.1

|precipitation colour = green
|source 1 = WRCC<ref name=WRCC>{{cite web|url=http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?ca4997|title=LIVERMORE, CALIFORNIA – Climate Summary|website=www.wrcc.dri.edu|access-date=June 5, 2018}}</ref> and pogodaiklimat.ru<ref>{{cite web|url=http://www.pogodaiklimat.ru/climate3/KLVK.htm|title=Климат Ливермора – Погода и климат|website=www.pogodaiklimat.ru|access-date=June 20, 2019}}</ref>
}}

===Adjacent counties===
The City and County of [[San Francisco, California]], borders the county on the west, and has a small land border with the city of [[Alameda, California]] due to land filling.<ref>{{cite news|url=https://www.kqed.org/news/11702058/why-is-part-of-alameda-island-in-san-francisco|title=Why Is Part of Alameda Island in San Francisco?|publisher=KQED|date=November 1, 2018}}</ref>

[[Santa Clara County, California|Santa Clara County]] borders the county on the south.

[[San Joaquin County, California|San Joaquin County]] borders the county on the east.

[[Contra Costa County, California|Contra Costa County]] borders the county on the north.

[[Stanislaus County, California|Stanislaus County]] borders the county on the easternmost end of its southern boundary for {{convert|250|ft|m}}.<ref>{{cite web|url=https://viewer.nationalmap.gov/advanced-viewer/|title = The National Map - Advanced Viewer}}</ref>

===National protected area===
* [[Don Edwards San Francisco Bay National Wildlife Refuge]] (part)

==Demographics==
{{US Census population
|1860= 8927
|1870= 24237
|1880= 62976
|1890= 93864
|1900= 130197
|1910= 246131
|1920= 344177
|1930= 474883
|1940= 513011
|1950= 740315
|1960= 908209
|1970= 1073184
|1980= 1105379
|1990= 1279182
|2000= 1443741
|2010= 1510271
|2020= 1682353
|estimate= 1649060
|estyear=2024
|estref=<ref>{{cite web|url=https://www.census.gov/quickfacts/alamedacountycalifornia|title=QuickFacts Alameda County, California|publisher=United States Census Bureau|access-date=May 9, 2025}}</ref>
|align-fn=center
|footnote=U.S. Decennial Census<ref name="DecennialCensus">{{cite web|url=https://www.census.gov/prod/www/decennial.html|title=Census of Population and Housing from 1790-2000|publisher=[[US Census Bureau]]|access-date=January 24, 2022}}</ref><br />1790–1960<ref>{{cite web|url=http://mapserver.lib.virginia.edu|title=Historical Census Browser|publisher=University of Virginia Library|access-date=September 24, 2015}}</ref> 1900–1990<ref>{{cite web|url=https://www.census.gov/population/cencounts/ca190090.txt|title=Population of Counties by Decennial Census: 1900 to 1990|publisher=United States Census Bureau|editor-last=Forstall|editor-first=Richard L.|date=March 27, 1995|access-date=September 24, 2015}}</ref><br />1990–2000<ref>{{cite web|url=https://www.census.gov/population/www/cen2000/briefs/phc-t4/tables/tab02.pdf|title=Census 2000 PHC-T-4. Ranking Tables for Counties: 1990 and 2000|publisher=United States Census Bureau|date=April 2, 2001|access-date=September 24, 2015}}</ref> 2010<ref name=2010CensusP2/> 2020<ref name=2020CensusP2/>
}}

===2020 census===
{| class="wikitable sortable" style="text-align:center;"
|+'''Alameda County, California – Racial and ethnic composition'''<br><small>{{nobold|''Note: the US Census treats Hispanic/Latino as an ethnic category. This table excludes Latinos from the racial categories and assigns them to a separate category. Hispanics/Latinos may be of any race.''}}</small>
!Race / Ethnicity <small>(''NH = Non-Hispanic'')</small>
!Pop 1980<ref>{{Cite web |title=California: 1980, General Social and Economic Characteristics, Part 1|website=[[United States Census Bureau]]|url=https://www2.census.gov/prod2/decennial/documents/1980a_caCs1-01.pdf|access-date=}}</ref>
!Pop 1990<ref>{{Cite web |title=California: 1990, Part 1 |website=[[United States Census Bureau]]|url=https://www2.census.gov/library/publications/decennial/1990/cp-1/cp-1-6-1.pdf |access-date=July 14, 2024}}</ref>
!Pop 2000<ref name=2000CensusP004>{{Cite web|title=P004: Hispanic or Latino, and Not Hispanic or Latino by Race – 2000: DEC Summary File 1 – Alameda County, California|url=https://data.census.gov/table?g=050XX00US06001&tid=DECENNIALSF12000.P004|website=[[United States Census Bureau]] |access-date= }}</ref>
!Pop 2010<ref name=2010CensusP2>{{Cite web|title=P2: Hispanic or Latino, and Not Hispanic or Latino by Race – 2010: DEC Redistricting Data (PL 94-171) – Alameda County, California|url=https://data.census.gov/cedsci/table?q=p2&g=050XX00US06001&tid=DECENNIALPL2010.P2|website=[[United States Census Bureau]] |access-date= }}</ref>
!style="background-color: #ffffb3;" | Pop 2020<ref name=2020CensusP2>{{Cite web|title=P2: Hispanic or Latino, and Not Hispanic or Latino by Race – 2020: DEC Redistricting Data (PL 94-171) – Alameda County, California|url=https://data.census.gov/cedsci/table?q=p2&g=050XX00US06001&tid=DECENNIALPL2020.P2|website=[[United States Census Bureau]] |access-date= }}</ref>
!% 1980
!% 1990
!% 2000
!% 2010
!style="background-color: #ffffb3;" |% 2020
|-
|[[Non-Hispanic or Latino whites|White]] alone (NH)
|675,338
|680,017
|591,095
|514,559
|style='background: #ffffe6; |472,277
|61.10%
|53.16%
|40.94%
|34.07%
|style='background: #ffffe6; |28.07%
|-
|[[Non-Hispanic or Latino African Americans|Black or African American]] alone (NH)
|200,950
|222,873
|211,124
|184,126
|style='background: #ffffe6; |159,499
|18.18%
|17.42%
|14.62%
|12.19%
|style='background: #ffffe6; |9.48%
|-
|[[Native Americans in the United States|Native American]] or [[Alaska Native]] alone (NH)
|7,446
|6,763
|5,306
|4,189
|style='background: #ffffe6; |4,131
|0.67%
|0.53%
|0.37%
|0.28%
|style='background: #ffffe6; |0.25%
|-
|[[Asian Americans|Asian]] alone (NH)
|85,899
|184,813
|292,673
|390,524
|style='background: #ffffe6; |540,511
|7.77%
|14.45%
|20.27%
|25.86%
|style='background: #ffffe6; |32.13%
|-
|[[Native Hawaiian]] or [[Pacific Islander Americans|Pacific Islander]] alone (NH)
|x
|x
|8,458
|11,931
|style='background: #ffffe6; |13,209
|x
|x
|0.59%
|0.79%
|style='background: #ffffe6; |0.79%
|-
|[[Race and ethnicity in the United States census|Other race]] alone (NH)
|5,784
|2,911
|4,676
|4,191
|style='background: #ffffe6; |10,440
|0.52%
|0.23%
|0.32%
|0.28%
|style='background: #ffffe6; |0.62%
|-
|[[Multiracial Americans|Mixed race or Multiracial]] (NH)
|x
|x
|56,499
|60,862
|style='background: #ffffe6; |88,537
|x
|x
|3.91%
|4.03%
|style='background: #ffffe6; |5.26%
|-
|[[Hispanic and Latino Americans|Hispanic or Latino]] (any race)
|129,962
|181,805
|273,910
|339,889
|style='background: #ffffe6; |393,749
|11.76%
|14.21%
|18.97%
|22.51%
|style='background: #ffffe6; |23.40%
|-
|'''Total'''
|'''1,105,379'''
|'''1,279,182'''
|'''1,443,741'''
|'''1,510,271'''
|style='background: #ffffe6; |'''1,682,353 '''
|'''100.00%'''
|'''100.00%'''
|'''100.00%'''
|'''100.00%'''
|style='background: #ffffe6; |'''100.00%'''
|}

===2014===
[[File:Ethnic Origins in Alameda County, CA.png|thumb|330x330px|Ethnic origins in Alameda County]]
A 2014 analysis by ''[[The Atlantic]]'' found Alameda County to be the fourth most racially diverse county in the United States, in terms of closest to equal representation of each racial and ethnic group,—behind [[Aleutians West Census Area, Alaska|Aleutians West Census Area]] and [[Aleutians East Borough, Alaska|Aleutians East Borough]] in Alaska, and [[Queens|Queens County]] in New York—as well as the most diverse county in California.<ref>{{Cite news|url=https://www.theatlantic.com/national/archive/2014/04/mapping-racial-diversity-by-county/361388/|title=The 5 U.S. Counties Where Racial Diversity Is Highest—and Lowest|last=Narula|first=Svati Kirsten|date=April 29, 2014|work=The Atlantic|access-date=May 8, 2017|language=en-US}}</ref> The 2020 census shows Alameda as having one of the highest Asian percentages and being one of two counties in the continental US, along with neighboring [[Santa Clara County, California]], to have an Asian plurality - consisting largely of Chinese, Indian and Filipino ancestry.<ref>{{cite web |url=http://www.justicemap.org/2020/index.php?gsLayer=plural&gfLon=-95.3&gfLat=39.6&giZoom=4&gsGeo=county&giAdvanced=1& |access-date=January 19, 2022| title=Justice Map - Visualize race and income data for your community }}</ref>

=== 2011 ===

{| class="wikitable sortable collapsible collapsed"
|-
! colspan="6" | Population, race, and income
|-
! scope="row" style="text-align: left;" | Total population<ref name="US-CB-B02001">U.S. Census Bureau. American Community Survey, 2011 American Community Survey 5-Year Estimates, Table B02001. [https://www.census.gov U.S. Census website]  . Retrieved October 26, 2013.</ref>
| colspan="2" | 1,494,876
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;White<ref name="US-CB-B02001" />
| 690,261
| 46.2%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Asian<ref name="US-CB-B02001" />
| 391,627
| 26.2%
|-
! scope="row" style="text-align: left;" | &nbsp;Hispanic or Latino (of any race)<ref name="US-CB-B03003">U.S. Census Bureau. American Community Survey, 2011 American Community Survey 5-Year Estimates, Table B03003. [https://www.census.gov U.S. Census website]  . Retrieved October 26, 2013.</ref>
| 332,103
| 22.2%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Black or African American<ref name="US-CB-B02001" />
| 186,326
| 12.5%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Some other race<ref name="US-CB-B02001" />
| 131,958
| 8.8%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Two or more races<ref name="US-CB-B02001" />
| 75,411
| 5.0%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Native Hawaiian or other Pacific Islander<ref name="US-CB-B02001" />
| 12,191
| 0.8%
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;American Indian or Alaska Native<ref name="US-CB-B02001" />
| 7,102
| 0.5%
|-
! scope="row" style="text-align: left;" | Per capita income<ref name="US-CB-B19301">U.S. Census Bureau. American Community Survey, 2011 American Community Survey 5-Year Estimates, Table B19301. [https://www.census.gov U.S. Census website]  . Retrieved October 21, 2013.</ref>
| colspan="2" | $34,937
|-
! scope="row" style="text-align: left;" | Median household income<ref name="US-CB-B19013">U.S. Census Bureau. American Community Survey, 2011 American Community Survey 5-Year Estimates, Table B19013. [https://www.census.gov U.S. Census website]  . Retrieved October 21, 2013.</ref>
| colspan="2" | $70,821
|-
! scope="row" style="text-align: left;" | Median family income<ref name="US-CB-B19113">U.S. Census Bureau. American Community Survey, 2011 American Community Survey 5-Year Estimates, Table B19113. [https://www.census.gov U.S. Census website]  . Retrieved October 21, 2013.</ref>
| colspan="2" | $87,012
|}

==== Places by population, race, and income ====

{| class="wikitable sortable mw-collapsible mw-collapsed" style="width: 100%;"
|-
! colspan="9" | Places by population and race
|-
! Place
! Type<ref name="US-CB">U.S. Census Bureau. American Community Survey, 2011 American Community Survey 5-Year Estimates. [https://www.census.gov U.S. Census website]  . Retrieved October 21, 2013.</ref>
! data-sort-type="number" | Population<ref name="US-CB-B02001"/>
! data-sort-type="number" | White<ref name="US-CB-B02001"/>
! data-sort-type="number" | Other<ref name="US-CB-B02001"/><br /><ref name="other" group=note>Other = Some other race + Two or more races</ref>
! data-sort-type="number" | Asian<ref name="US-CB-B02001"/>
! data-sort-type="number" | Black or African<br />American<ref name="US-CB-B02001"/>
! data-sort-type="number" | Native American<ref name="US-CB-B02001"/><br /><ref name="na" group=note>Native American = Native Hawaiian or other Pacific Islander + American Indian or Alaska Native</ref>
! data-sort-type="number" | Hispanic or Latino<br />(of any race)<ref name="US-CB-B03003"/>
|-
| [[Alameda, California|Alameda]] || [[List of cities and towns in California|City]] || 73,239 || 49.5% || 9.8% || 33.1% || 6.7% || 0.9% || 11.8%
|-
| [[Albany, California|Albany]] || [[List of cities and towns in California|City]] || 18,217 || 60.7% || 7.0% || 29.1% || 3.0% || 0.1% || 9.7%
|-
| [[Ashland, California|Ashland]] || [[Census-designated place|CDP]] || 22,106 || 53.4% || 11.9% || 16.4% || 17.0% || 1.3% || 46.7%
|-
| [[Berkeley, California|Berkeley]] || [[List of cities and towns in California|City]] || 111,008 || 61.5% || 8.0% || 20.6% || 9.3% || 0.6% || 10.5%
|-
| [[Castro Valley, California|Castro Valley]] || [[Census-designated place|CDP]] || 60,882 || 62.9% || 7.9% || 21.7% || 6.8% || 0.8% || 17.4%
|-
| [[Cherryland, California|Cherryland]] || [[Census-designated place|CDP]] || 14,394 || 46.8% || 31.1% || 9.0% || 8.6% || 4.5% || 55.9%
|-
| [[Dublin, California|Dublin]] || [[List of cities and towns in California|City]] || 44,171 || 57.5% || 8.7% || 26.2% || 6.9% || 0.7% || 12.9%
|-
| [[Emeryville, California|Emeryville]] || [[List of cities and towns in California|City]] || 9,698 || 44.1% || 5.7% || 36.3% || 13.8% || 0.2% || 8.8%
|-
| [[Fairview, California|Fairview]] || [[Census-designated place|CDP]] || 9,597 || 49.2% || 13.5% || 18.1% || 17.7% || 1.5% || 18.5%
|-
| [[Fremont, California|Fremont]] || [[List of cities and towns in California|City]] || 211,748 || 33.9% || 12.8% || 49.0% || 3.3% || 1.1% || 15.4%
|-
| [[Hayward, California|Hayward]] || [[List of cities and towns in California|City]] || 142,936 || 36.9% || 24.9% || 23.6% || 11.4% || 3.2% || 39.9%
|-
| [[Livermore, California|Livermore]] || [[List of cities and towns in California|City]] || 79,710 || 78.9% || 8.4% || 10.3% || 1.8% || 0.5% || 19.0%
|-
| [[Newark, California|Newark]] || [[List of cities and towns in California|City]] || 42,322 || 42.1% || 24.4% || 26.2% || 4.3% || 3.0% || 35.2%
|-
| [[Oakland, California|Oakland]] || [[List of cities and towns in California|City]] || 389,397 || 39.0% || 15.7% || 16.1% || 28.1% || 1.1% || 25.0%
|-
| [[Piedmont, California|Piedmont]] || [[List of cities and towns in California|City]] || 10,640 || 76.1% || 3.4% || 19.5% || 0.9% || 0.1% || 3.9%
|-
| [[Pleasanton, California|Pleasanton]] || [[List of cities and towns in California|City]] || 69,220 || 68.0% || 6.2% || 22.9% || 2.5% || 0.4% || 10.6%
|-
| [[San Leandro, California|San Leandro]] || [[List of cities and towns in California|City]] || 83,877 || 44.9% || 10.2% || 29.6% || 13.4% || 1.9% || 26.0%
|-
| [[San Lorenzo, California|San Lorenzo]] || [[Census-designated place|CDP]] || 24,096 || 54.1% || 17.2% || 20.8% || 6.5% || 1.4% || 35.9%
|-
| [[Sunol, California|Sunol]] || [[Census-designated place|CDP]] || 760 || 84.3% || 11.6% || 4.1% || 0.0% || 0.0% || 15.8%
|-
| [[Union City, California|Union City]] || [[List of cities and towns in California|City]] || 68,830 || 21.5% || 17.8% || 53.3% || 6.2% || 1.2% || 21.5%
|}

{| class="wikitable sortable mw-collapsible mw-collapsed" style="width: 100%;"
|-
! colspan="6" | Places by population and income
|-
! Place
! Type<ref name="US-CB" />
! Population<ref name="US-CB-B01003">U.S. Census Bureau. American Community Survey, 2011 American Community Survey 5-Year Estimates, Table B01003. [https://www.census.gov U.S. Census website]  . Retrieved October 21, 2013.</ref>
! data-sort-type="currency" | Per capita income<ref name="US-CB-B19301" />
! data-sort-type="currency" | Median household income<ref name="US-CB-B19013" />
! data-sort-type="currency" | Median family income<ref name="US-CB-B19113" />
|-
| [[Alameda, California|Alameda]] || [[List of cities and towns in California|City]] || 73,239 || $39,160 || $75,832 || $93,349
|-
| [[Albany, California|Albany]] || [[List of cities and towns in California|City]] || 18,217 || $37,552 || $72,479 || $87,500
|-
| [[Ashland, California|Ashland]] || [[Census-designated place|CDP]] || 22,106 || $20,357 || $48,026 || $53,038
|-
| [[Berkeley, California|Berkeley]] || [[List of cities and towns in California|City]] || 111,008 || $38,896 || $60,908 || $102,976
|-
| [[Castro Valley, California|Castro Valley]] || [[Census-designated place|CDP]] || 60,882 || $38,535 || $82,370 || $97,628
|-
| [[Cherryland, California|Cherryland]] || [[Census-designated place|CDP]] || 14,394 || $19,610 || $50,987 || $48,120
|-
| [[Dublin, California|Dublin]] || [[List of cities and towns in California|City]] || 44,171 || $41,197 || $111,481 || $121,380
|-
| [[Emeryville, California|Emeryville]] || [[List of cities and towns in California|City]] || 9,698 || $52,258 || $69,274 || $99,954
|-
| [[Fairview, California|Fairview]] || [[Census-designated place|CDP]] || 9,597 || $38,267 || $85,288 || $97,969
|-
| [[Fremont, California|Fremont]] || [[List of cities and towns in California|City]] || 211,748 || $38,752 || $98,513 || $109,853
|-
| [[Hayward, California|Hayward]] || [[List of cities and towns in California|City]] || 142,936 || $24,987 || $62,115 || $69,044
|-
| [[Livermore, California|Livermore]] || [[List of cities and towns in California|City]] || 79,710 || $41,741 || $96,322 || $108,406
|-
| [[Newark, California|Newark]] || [[List of cities and towns in California|City]] || 42,322 || $29,375 || $81,777 || $84,244
|-
| [[Oakland, California|Oakland]] || [[List of cities and towns in California|City]] || 389,397 || $31,675 || $51,144 || $58,237
|-
| [[Piedmont, California|Piedmont]] || [[List of cities and towns in California|City]] || 10,640 || $92,232 || $199,304 || $221,875
|-
| [[Pleasanton, California|Pleasanton]] || [[List of cities and towns in California|City]] || 69,220 || $50,745 || $118,713 || $136,464
|-
| [[San Leandro, California|San Leandro]] || [[List of cities and towns in California|City]] || 83,877 || $27,878 || $61,857 || $72,080
|-
| [[San Lorenzo, California|San Lorenzo]] || [[Census-designated place|CDP]] || 24,096 || $25,553 || $73,053 || $76,365
|-
| [[Sunol, California|Sunol]] || [[Census-designated place|CDP]] || 760 || $62,651 || $72,656 || $86,250
|-
| [[Union City, California|Union City]] || [[List of cities and towns in California|City]] || 68,830 || $29,612 || $82,634 || $91,176
|}

===2010===
The [[2010 United States census]] reported that Alameda County had a population of 1,510,271. The population density was {{convert|2,047.6|PD/sqmi|PD/km2|sp=us|adj=off}}. The racial makeup of Alameda County was 649,122 (43.0%) [[White (U.S. Census)|White]], 190,451 (12.6%) [[African American (U.S. census)|African American]], 9,799 (0.6%) [[Native American (U.S. Census)|Native American]], 394,560 (26.1%) [[Asian (U.S. Census)|Asian]] (9.7% Chinese, 5.5% Filipino, 4.8% Indian, 2.0% Vietnamese, 1.2% Korean, 0.8% Japanese, 2.2% Other Asian), 12,802 (0.8%) [[Pacific Islander (U.S. Census)|Pacific Islander]], 162,540 (10.8%) from [[Race (United States Census)|other races]], and 90,997 (6.0%) from two or more races.  [[Hispanic (U.S. Census)|Hispanic]] or [[Latino (U.S. Census)|Latino]] of any race were 339,889 persons (22.5%): 16.4% Mexican, 0.8% Puerto Rican, 0.2% Cuban, 5.1% Other Hispanic.<ref>{{USCensus2010CA}}</ref>
{|
|-
|align="left" |
{| class="wikitable sortable collapsible collapsed" style="margin-left:auto;margin-right:auto;text-align: right;font-size: 90%;"
! Demographic profile<ref>{{Cite web|url=http://www.bayareacensus.ca.gov|title=Bay Area Census|website=www.bayareacensus.ca.gov}}</ref>
! 2010
|-
|align="left" | Total Population || 1,510,271 – 100.0%
|-
|align="left" | One Race || 1,419,274 – 94.0%
|-
|align="left" | Not Hispanic or Latino || 1,170,382 – 77.5%
|-
|align="left" | White alone || 514,559 – 34.1%
|-
|align="left" | Black or African American alone || 184,126 – 12.2%
|-
|align="left" | American Indian and Alaska Native alone || 4,189 – 0.3%
|-
|align="left" | Asian alone || 390,524 – 25.9%
|-
|align="left" | Native Hawaiian and Other Pacific Islander alone || 11,931 – 0.8%
|-
|align="left" | Some other race alone || 4,191 – 0.3%
|-
|align="left" | Two or more races alone || 60,862 – 4.0%
|-
|align="left" | Hispanic or Latino (of any race) || 339,889 – 22.5%
|}
|}

{| class="wikitable collapsible collapsed"
|-
!colspan="10"|Population reported at [[2010 United States census]]
|- style="text-align:center;"
|'''The County''' ||'''Total<br />Population'''||'''[[White (U.S. Census)|White]]''' ||'''[[African American (U.S. census)|African<br />American]]''' ||'''[[Native American (U.S. Census)|Native<br />American]]''' ||'''[[Asian (U.S. Census)|Asian]]''' ||'''[[Pacific Islander (U.S. Census)|Pacific<br />Islander]]''' ||'''[[Race (United States Census)|other<br />races]]''' ||'''two or<br />more races''' ||'''[[Hispanic (U.S. Census)|Hispanic]]<br />or [[Latino (U.S. Census)|Latino]]<br />(of any race)'''
|-
|''' Alameda County'''
|align="right"|1,510,271||align="right"|649,122||align="right"|190,451||align="right"|9,799||align="right"|394,560||align="right"|12,802||align="right"|162,540||align="right"|90,997||align="right"|339,889
|- style="text-align:center;"
|'''[[Incorporated city|Incorporated<br />cities]]''' ||'''Total<br />Population'''||'''[[White (U.S. Census)|White]]''' ||'''[[African American (U.S. census)|African<br />American]]''' ||'''[[Native American (U.S. Census)|Native<br />American]]''' ||'''[[Asian (U.S. Census)|Asian]]''' ||'''[[Pacific Islander (U.S. Census)|Pacific<br />Islander]]''' ||'''[[Race (United States Census)|other<br />races]]''' ||'''two or<br />more races''' ||'''[[Hispanic (U.S. Census)|Hispanic]]<br />or [[Latino (U.S. Census)|Latino]]<br />(of any race)'''
|-
|''' [[Alameda, California|Alameda]]'''
|align="right"|73,812||align="right"|37,460||align="right"|4,759||align="right"|426||align="right"|23,058||align="right"|381||align="right"|2,463||align="right"|5,265||align="right"|8,092
|-
|''' [[Albany, California|Albany]]'''
|align="right"|18,539||align="right"|10,128||align="right"|645||align="right"|88||align="right"|5,790||align="right"|37||align="right"|607||align="right"|1,244||align="right"|1,891
|-
|'''[[Berkeley, California|Berkeley]]'''
|align="right"|112,580||align="right"|66,996||align="right"|11,241||align="right"|479||align="right"|21,690||align="right"|186||align="right"|4,994||align="right"|6,994||align="right"|12,209
|-
|'''[[Dublin, California|Dublin]]'''
|align="right"|46,036||align="right"|23,634||align="right"|4,347||align="right"|246||align="right"|12,321||align="right"|287||align="right"|2,458||align="right"|2,743||align="right"|6,663
|-
|'''[[Emeryville, California|Emeryville]]'''
|align="right"|10,080||align="right"|4,490||align="right"|1,764||align="right"|44||align="right"|2,775||align="right"|16||align="right"|348||align="right"|643||align="right"|927
|-
|'''[[Fremont, California|Fremont]]'''
|align="right"|214,089||align="right"|70,320||align="right"|7,103||align="right"|976||align="right"|108,332||align="right"|1,169||align="right"|13,605||align="right"|12,584||align="right"|31,698
|-
|'''[[Hayward, California|Hayward]]'''
|align="right"|144,186||align="right"|49,309||align="right"|17,099||align="right"|1,396||align="right"|31,666||align="right"|4,535||align="right"|30,004||align="right"|10,177||align="right"|58,730
|-
|'''[[Livermore, California|Livermore]]'''
|align="right"|80,968||align="right"|60,418||align="right"|1,702||align="right"|476||align="right"|6,802||align="right"|277||align="right"|6,960||align="right"|4,333||align="right"|16,920
|-
|'''[[Newark, California|Newark]]'''
|align="right"|42,573||align="right"|17,566||align="right"|2,002||align="right"|279||align="right"|11,571||align="right"|621||align="right"|7,735||align="right"|2,799||align="right"|14,994
|-
|'''[[Oakland, California|Oakland]]'''
|align="right"|390,724||align="right"|134,925||align="right"|109,471||align="right"|3,040||align="right"|65,811||align="right"|2,222||align="right"|53,378||align="right"|21,877||align="right"|99,068
|-
|'''[[Piedmont, California|Piedmont]]'''
|align="right"|10,667||align="right"|7,917||align="right"|144||align="right"|6||align="right"|1,939||align="right"|13||align="right"|94||align="right"|554||align="right"|421
|-
|'''[[Pleasanton, California|Pleasanton]]'''
|align="right"|70,285||align="right"|47,058||align="right"|1,190||align="right"|226||align="right"|16,322||align="right"|134||align="right"|2,002||align="right"|3,353||align="right"|7,264
|-
|'''[[San Leandro, California|San Leandro]]'''
|align="right"|84,950||align="right"|31,946||align="right"|10,437||align="right"|669||align="right"|25,206||align="right"|642||align="right"|11,295||align="right"|4,755||align="right"|23,237
|-
|'''[[Union City, California|Union City]]'''
|align="right"|69,516||align="right"|16,640||align="right"|4,402||align="right"|329||align="right"|35,363||align="right"|892||align="right"|7,253||align="right"|4,637||align="right"|15,895
|- style="text-align:center;"
|'''[[Census-designated place|Census-designated<br />places]]''' ||'''Total<br />Population'''||'''[[White (U.S. Census)|White]]''' ||'''[[African American (U.S. census)|African<br />American]]''' ||'''[[Native American (U.S. Census)|Native<br />American]]''' ||'''[[Asian (U.S. Census)|Asian]]''' ||'''[[Pacific Islander (U.S. Census)|Pacific<br />Islander]]''' ||'''[[Race (United States Census)|other<br />races]]''' ||'''two or<br />more races''' ||'''[[Hispanic (U.S. Census)|Hispanic]]<br />or [[Latino (U.S. Census)|Latino]]<br />(of any race)'''
|-
|'''[[Ashland, California|Ashland]]'''
|align="right"|21,925||align="right"|6,705||align="right"|4,269||align="right"|232||align="right"|4,031||align="right"|260||align="right"|5,124||align="right"|1,304||align="right"|9,394
|-
|'''[[Castro Valley, California|Castro Valley]]'''
|align="right"|61,388||align="right"|35,602||align="right"|4,260||align="right"|329||align="right"|13,140||align="right"|417||align="right"|3,757||align="right"|3,883||align="right"|10,689
 |-
|'''[[Cherryland, California|Cherryland]]'''
|align="right"|14,728||align="right"|6,035||align="right"|1,698||align="right"|200||align="right"|1,404||align="right"|310||align="right"|4,016||align="right"|1,065||align="right"|7,955
 |-
|'''[[Fairview, California|Fairview]]'''
|align="right"|10,003||align="right"|4,499||align="right"|2,105||align="right"|76||align="right"|1,525||align="right"|129||align="right"|913||align="right"|756||align="right"|2,171
|-
|'''[[San Lorenzo, California|San Lorenzo]]'''
|align="right"|23,452||align="right"|11,115||align="right"|1,136||align="right"|228||align="right"|5,054||align="right"|182||align="right"|4,207||align="right"|1,530||align="right"|8,843
|-
|'''[[Sunol, California|Sunol]]'''
|align="right"|913||align="right"|780||align="right"|1||align="right"|6||align="right"|48||align="right"|7||align="right"|19||align="right"|52||align="right"|91
|- style="text-align:center;"
|'''Other<br />[[unincorporated area]]s''' ||'''Total<br />Population'''||'''[[White (U.S. Census)|White]]''' ||'''[[African American (U.S. census)|African<br />American]]''' ||'''[[Native American (U.S. Census)|Native<br />American]]''' ||'''[[Asian (U.S. Census)|Asian]]''' ||'''[[Pacific Islander (U.S. Census)|Pacific<br />Islander]]''' ||'''[[Race (United States Census)|other<br />races]]''' ||'''two or<br />more races''' ||'''[[Hispanic (U.S. Census)|Hispanic]]<br />or [[Latino (U.S. Census)|Latino]]<br />(of any race)'''
|-
|All others not CDPs (combined)
|align="right"|8,857||align="right"|5,579||align="right"|676||align="right"|48||align="right"|712||align="right"|85||align="right"|1,308||align="right"|449||align="right"|2,737
|}

===2000===
As of the [[census]]<ref name="GR8">{{cite web|url=https://www.census.gov |publisher=[[United States Census Bureau]] |access-date=May 14, 2011 |title=U.S. Census website  }}</ref> of 2000, there were 1,443,741 people, 523,366 households, out of which 32.6% had children under the age of 18 living within them, 47.0% [[Marriage|married couples]] living together, 13.0% had a female householder with no husband present, and 35.2% were non-families. 26.0% of all households were made up of individuals, and 7.3% had someone living alone who was 65 years of age or older. The average household size was 2.71 and the average family size was 3.31.

In the county, the population was spread out, with 24.6% under the age of 18, 9.6% from 18 to 24, 33.9% from 25 to 44, 21.7% from 45 to 64, and 10.2% who were 65 years of age or older. The median age was 34 years. For every 100 females there were 96.60 males. For every 100 females age 18 and over, there were 94.00 males.

The median income for a household in the county was $55,946, and the median income for a family was $65,857 (these figures had risen to $66,430 and $81,341 respectively as of a 2007 estimate<ref>{{Cite web|url=https://factfinder.census.gov/faces/nav/jsf/pages/community_facts.xhtml|archive-date=February 11, 2020|archive-url=https://archive.today/20200211175836/http://factfinder.census.gov/servlet/ACSSAFFFacts?_event=ChangeGeoContext&geo_id=05000US06001&_geoContext=&_street=&_county=alameda&_cityTown=alameda&_state=04000US06&_zip=&_lang=en&_sse=on&ActiveGeoDiv=&_useEV=&pctxt=fph&pgsl=010&_submenuId=factsheet_1&ds_name=ACS_2007_3YR_SAFF&_ci_nbr=null&qr_name=null&reg=null:null&_keyword=&_industry=|url-status=dead|title=American FactFinder - Community Facts > Alameda County, California}}</ref>). Males had a median income of $47,425 versus $36,921 for females. The [[per capita income]] for the county was $26,680. About 7.7% of families and 11.0% of the population were below the [[poverty line]], including 13.5% of those under age 18 and 8.1% of those age 65 or over.

In 2000, the largest denominational group was the [[Catholic]]s (with 306,437 adherents).<ref name="thearda">{{cite web |url=http://www.thearda.com/mapsReports/reports/counties/06001_2000.asp|title=County Membership Reports |access-date=August 22, 2011 |work= thearda.com | archive-url= https://web.archive.org/web/20110710230449/http://www.thearda.com/mapsReports/reports/counties/06001_2000.asp| archive-date= July 10, 2011 | url-status= live}}</ref> The largest religious bodies were the [[Catholic Church]] (with 306,437 members) and [[Judaism]] (with 32,500 members).<ref name="thearda" />

===2019 United States Census Bureau American Community Survey estimates===
{| class="cx-linter-tag"
|-
| valign="top" |
{{Pie chart
 | thumb   = left
 | caption = '''Racial Makeup of Alameda County (2019)'''<ref name=CensusACS2019 />
 | label1 = White alone
 | value1 = 38.84| color2=#36A
 | label2 = Black alone
 | value2 = 10.66| color1=#6A5
 | label3 = Native American alone
 | value3 = 0.76| color3=#FF33AC
 | label4 = Asian Alone
 | value4 = 31.13| color4=#1A9
 | label5 = Pacific Islander Alone
 | value5 = 0.81| color5=#E17720
 | label6 = Other race alone
 | value6 = 11.45| color6=#F0FF00
 | label7 = Two or more races
 | value7 = 6.35| color7=#64ECDF
 }}
| valign="top" |
{{Pie chart
 | caption= '''Racial Makeup of Alameda County excluding Hispanics from racial categories (2019)'''<ref name=CensusACS2019 /><br /> ''NH=Non-Hispanic''
 | thumb   = right
 | label1 = White alone
 | value1 = 30.43| color2=#36A
 | label2 = Black alone
 | value2 = 10.33| color1=#6A5
 | label3 = Native American alone
 | value3 = 0.33| color3=#FF33AC
 | label4 = Asian Alone
 | value4 = 30.93| color4=#1A9
 | label5 = Pacific Islander Alone
 | value5 = 0.77| color5=#E17720
 | label6 = Other race alone
 | value6 = 0.47| color6=#F0FF00
 | label7 = Two or more races
 | value7 = 4.41| color7=#64ECDF
 | label8 = Hispanic Any Race
 | value8 = 22.32| color8=#9400D3
 }}
| valign="top" |
{{Pie chart
 | thumb   = right
 | caption = '''Racial Makeup of Hispanics in Alameda County''' (2019)<ref name=CensusACS2019 />
 | label1 = White alone
 | value1 = 37.69| color2=#36A
 | label2 = Black alone
 | value2 = 1.48| color1=#6A5
 | label3 = Native American alone
 | value3 = 1.91 | color3=#FF33AC
 | label4 = Asian alone
 | value4 = 0.89 | color4=#1A9
 | label5 = Pacific Islander alone
 | value5 = 0.17| color5=#E17720
 | label6 = Other race alone
 | value6 = 49.16 | color6=#F0FF00
 | label7 = Two or more races
 | value7 = 8.69 | color7=#64ECDF
 }}
|}

According to 2019 US Census Bureau estimates, Alameda County's population was 38.8% [[White American|White]] (30.4% [[Non-Hispanic White]] and 8.4% [[Hispanic White]]), 10.7% Black or [[African American]], 31.1% [[Asian American|Asian]], 11.5% Some Other Race, 0.8% [[Native Americans in the United States|Native American]] and [[Alaskan Native]], 0.8% [[Pacific Islander]] and 6.4% from [[Multiracial American|two or more races]].<ref name=CensusACS2019>{{cite web|url=https://data.census.gov/cedsci/table?q=B03002&g=0500000US06001&tid=ACSDT1Y2019.B03002&hidePreview=true|title=B03002 HISPANIC OR LATINO ORIGIN BY RACE – Alameda County, California – 2019 American Community Survey 1-Year Estimates|date=July 1, 2019 |publisher=[[U.S. Census Bureau]] |access-date=January 30, 2021}}</ref>

The White population continues to remain the largest racial category in Alameda County and includes the 37.7% of Hispanics who self-identify as White. The remainder of Hispanics self-identify as Other Race (49.2%), Multiracial (8.7%), American Indian and Alaskan Native (1.9%), Black (1.5%), Asian (0.9%), and Hawaiian and Pacific Islander (0.2%).<ref name=CensusACS2019 />

The Black population continues to decline and at 10.7% (including [[Black Hispanics]])<ref name=CensusACS2019 /> is below the national average of 12.8% (including Black Hispanics).<ref>{{cite web|url=https://data.census.gov/cedsci/table?g=0100000US&tid=ACSDT1Y2019.B03002&hidePreview=true|title=B03002 HISPANIC OR LATINO ORIGIN BY RACE – United States – 2019 American Community Survey 1-Year Estimates|date=July 1, 2019 |publisher=[[U.S. Census Bureau]] |access-date=January 28, 2021}}</ref>  The Black population peaked in the 1980 Census at 18.4%.<ref>{{cite web|title=Alameda County Decennial Census data   |website=Bay Area Census|url= http://www.bayareacensus.ca.gov/counties/AlamedaCounty70.htm |archive-url= https://web.archive.org/web/20041011020303/http://www.bayareacensus.ca.gov/counties/AlamedaCounty70.htm |url-status= dead |archive-date= October 11, 2004 |access-date=January 28, 2020}}</ref> Alameda county has the 2nd highest percentage of Black residents in California after [[Solano County]] at 13.4%.

If Hispanics are treated as a separate category from race, Alameda County's population was 30.4% [[White American|White]], 30.9% [[Asian American|Asian]], 22.3% [[Hispanic and Latino Americans|Hispanic-Latino]], 10.3% Black or [[African American]], 0.5% Some Other Race, 0.3% [[Native Americans in the United States|Native American]] and [[Alaskan Native]], 0.8% [[Pacific Islander]] and 4.4% from [[Multiracial American|two or more races]].<ref name=CensusACS2018>{{cite web|url=https://data.census.gov/cedsci/table?q=&tid=ACSDT1Y2018.B03002&lastDisplayedRow=20&hidePreview=true&vintage=2018&layer=county&cid=B03002_001E&g=0500000US06001|title=B03002 HISPANIC OR LATINO ORIGIN BY RACE – Alameda County, California – 2018 American Community Survey 1-Year Estimates|date=July 1, 2018 |publisher=[[U.S. Census Bureau]] |access-date=January 28, 2020}}</ref>

Asian Americans are now the largest racial/ethnic group at 30.9% (excluding Asian Hispanics).<ref name=CensusACS2019 />

White Non-Hispanic Americans are the largest minority group at 30.4% of the population.<ref name=CensusACS2019 />

By ethnicity, 22.3% of the total population is [[Hispanic and Latino Americans|Hispanic-Latino]] (of any race) and 77.7% is Non-Hispanic (of any race). If treated as a category separate from race, Hispanics are the third largest minority group in Alameda County.<ref name=CensusACS2019 />

The largest ancestry group of Hispanics in Alameda County (2018) are of [[Mexican American|Mexican]] descent (72.9% of Hispanics) followed by [[Salvadoran Americans|Salvadoran]] descent (5.5% of Hispanics), [[Guatemalan American|Guatemalan]] descent (3.9%), [[Puerto Ricans|Puerto Rican]] descent (3.4%), [[Spanish Americans|Spaniard]] descent (2.0%), [[Nicaraguan Americans|Nicaraguan]] descent (1.7%), [[Peruvian Americans|Peruvian]] descent (1.4%), [[Cuban Americans|Cuban]] descent (1.2%), [[Colombian Americans|Colombian]] descent (1.1%), and those of other Hispanic ethnicity or of mixed Hispanic ethnicity (6.9%).<ref name=CensusACS2018-B03001>{{cite web|url=https://data.census.gov/cedsci/table?q=mexican&tid=ACSDT1Y2018.B03001&lastDisplayedRow=30&hidePreview=true&vintage=2018&layer=state%3DS0506_C01_001E&y=2018&table=B03001&mode=&t=&g=0500000US06001|title=B03001 HISPANIC OR LATINO ORIGIN BY SPECIFIC ORIGIN – Alameda County, California – 2018 American Community Survey 1-Year Estimates|date=July 1, 2018 |publisher=[[U.S. Census Bureau]] |access-date=January 28, 2020}}</ref>

== Crime ==

The following table includes the number of incidents reported and the rate per 1,000 persons for each type of offense.

{| class="wikitable collapsible collapsed"
|-
! colspan="3" | Population and crime rates in 2009
|-
! scope="row" style="text-align: left;" | Population<ref name="US-CB-B02001"/>
| colspan="2" | 1,494,876
|-
! scope="row" style="text-align: left;" | Violent crime<ref name="CA-DOJ-T11">Office of the Attorney General, Department of Justice, State of California. [http://stats.doj.ca.gov/cjsc_stats/prof09/00/11.pdf Table 11: Crimes – 2009] {{webarchive |url=https://web.archive.org/web/20131202222315/http://stats.doj.ca.gov/cjsc_stats/prof09/00/11.pdf |date=December 2, 2013 }}. Retrieved November 14, 2013.</ref>
| 11,189 || 7.48
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Homicide<ref name="CA-DOJ-T11"/>
| 138 || 0.09
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Forcible rape<ref name="CA-DOJ-T11"/>
| 553 || 0.37
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Robbery<ref name="CA-DOJ-T11"/>
| 5,215 || 3.49
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Aggravated assault<ref name="CA-DOJ-T11"/>
| 5,283 || 3.53
|-
! scope="row" style="text-align: left;" | Property crime<ref name="CA-DOJ-T11"/>
| 33,395 || 22.34
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Burglary<ref name="CA-DOJ-T11"/>
| 11,478 || 7.68
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Larceny-theft<ref name="CA-DOJ-T11"/><ref group=note name="LT-note">Only larceny-theft cases involving property over $400 in value are reported as property crimes.</ref>
| 32,102 || 21.47
|-
! scope="row" style="text-align: left;" | &nbsp;&nbsp;Motor vehicle theft<ref name="CA-DOJ-T11"/>
| 12,768 || 8.54
|-
! scope="row" style="text-align: left;" | Arson<ref name="CA-DOJ-T11"/>
| 457 || 0.31
|}

=== Cities by population and crime rates ===

{| class="wikitable collapsible collapsed sortable" style="width: 100%;"
|-
! colspan="9" | Cities by population and crime rates in 2012
|-
! City
! data-sort-type="number" | Population<ref name="FBI-UCR-T8">United States Department of Justice, Federal Bureau of Investigation. [https://www.fbi.gov/about-us/cjis/ucr/crime-in-the-u.s/2012/crime-in-the-u.s.-2012/tables/8tabledatadecpdf/table-8-state-cuts/table_8_offenses_known_to_law_enforcement_by_california_by_city_2012.xls Crime in the United States, 2012, Table 8 (California)]. Retrieved November 14, 2013.</ref>
! data-sort-type="number" | Violent crimes<ref name="FBI-UCR-T8"/>
! data-sort-type="number" | Violent crime rate<br />per 1,000 persons
! data-sort-type="number" | Property crimes<ref name="FBI-UCR-T8"/>
! data-sort-type="number" | Property crime rate<br />per 1,000 persons
|-
| [[Alameda, California|Alameda]] || 75,467 || 160 || 2.12 || 1,892 || 25.07
|-
| [[Albany, California|Albany]] || 18,960 || 35 || 1.85 || 537 || 28.32
|-
| [[Berkeley, California|Berkeley]] || 114,961 || 487 || 4.24 || 5,696 || 49.55
|-
| [[Dublin, California|Dublin]] || 49,890 || 84 || 1.79 || 731 || 15.55
|-
| [[Emeryville, California|Emeryville]] || 10,309 || 175 || 16.98 || 1,735 || 168.30
|-
| [[Fremont, California|Fremont]] || 218,927 || 306 || 1.40 || 4,259 || 19.45
|-
| [[Hayward, California|Hayward]] || 147,424 || 613 || 4.16 || 4,792 || 32.50
|-
| [[Livermore, California|Livermore]] || 82,800 || 301 || 3.64 || 1,805 || 21.80
|-
| [[Newark, California|Newark]] || 43,539 || 169 || 3.88 || 1,349 || 30.98
|-
| [[Oakland, California|Oakland]] || 399,487 || 7,963 || 19.93 || 26,342 || 65.94
|-
| [[Piedmont, California|Piedmont]] || 10,909 || 13 || 1.19 || 333 || 30.53
|-
| [[Pleasanton, California|Pleasanton]] || 71,875 || 49 || 0.68 || 1,279 || 17.79
|-
| [[San Leandro, California|San Leandro]] || 86,869 || 437 || 5.03 || 3,585 || 41.27
|-
| [[Union City, California|Union City]] || 71,089 || 235 || 3.31 || 1,808 || 25.43
|}

==Education==
The [[Alameda County Office of Education]] oversees seventeen K–12 school districts and one K–8 district in Alameda County. In all, there are approximately 10,000 teachers serving 225,000 students. The ACOE also services three community college districts with a total enrollment of approximately 55,000 students.

The [[Alameda County Library]] operates libraries in the cities of [[Albany, California|Albany]], [[Dublin, California|Dublin]], [[Fremont, California|Fremont]], [[Newark, California|Newark]] and [[Union City, California|Union City]] and the unincorporated communities of [[Castro Valley, California|Castro Valley]] and [[San Lorenzo, California|San Lorenzo]]. The cities of Alameda, Berkeley, Hayward, Livermore, Oakland, San Leandro, and Pleasanton have their own library systems.

===Colleges and universities===
Alameda County is home to the [[University of California, Berkeley]], the flagship campus of the [[University of California]] system, and one of the largest and most prestigious research universities in the world.

Other colleges and universities located within Alameda county include:
* [[Berkeley City College]]
* [[California State University, East Bay]], one of the campuses of the [[California State University]] system
* [[Chabot College]], a two-year community college, part of the [[Chabot-Las Positas Community College District]]
* [[College of Alameda]], a two-year community college, part of the [[Peralta Community College District]] of northern Alameda County
* [[Graduate Theological Union]], a consortium of several Bay Area seminaries, affiliated with the [[University of California, Berkeley]].
* [[Laney College]], a two-year community college, part of the Peralta Community College system
* [[Las Positas College]]
* [[Merritt College]], a two-year community college, part of the Peralta Community College system
* [[Mills College at Northeastern University]], a private 4 year women's college and coeducational graduate school
* [[Ohlone College]], part of the [[Ohlone Community College District]]
* [[Samuel Merritt University]]

Other local colleges and universities which have now closed include:
* [[SAE Expression College]], a for-profit school specializing in creative media
* [[Holy Names University]]

===Public schools===
;School districts<ref>{{cite web|url=https://www2.census.gov/geo/maps/DC2020/PL20/st06_ca/schooldistrict_maps/c06001_alameda/DC20SD_C06001.pdf|title=2020 CENSUS - SCHOOL DISTRICT REFERENCE MAP: Alameda County, CA|publisher=[[U.S. Census Bureau]]|accessdate=July 19, 2022}} - [https://www2.census.gov/geo/maps/DC2020/PL20/st06_ca/schooldistrict_maps/c06001_alameda/DC20SD_C06001_SD2MS.txt Text list]</ref>

K–12 unified school districts:
{{Div col|colwidth=30em}}
* [[Alameda Unified School District]]
* [[Albany Unified School District]]
* [[Berkeley Unified School District]]
* [[Castro Valley Unified School District]]
* [[Dublin Unified School District]]
* [[Emery Unified School District]]
* [[Fremont Unified School District]]
* [[Hayward Unified School District]]
* [[Livermore Valley Joint Unified School District]]
* [[New Haven Unified School District]]
* [[Newark Unified School District]]
* [[Oakland Unified School District]]
* [[Piedmont Unified School District]]
* [[Pleasanton Unified School District]]
* [[San Leandro Unified School District]]
* [[San Lorenzo Unified School District]]
* [[Sunol Glen Unified School District]]
{{div col end}}

Others:
* [[Lammersville Joint Unified School District]] (high)
* [[Mountain House Elementary School District]] (elementary)

; State-operated schools
* [[California School for the Blind]]
* [[California School for the Deaf, Riverside]]

==Arts==
The [[Alameda County Arts Commission]], a division of the county administration, under the [[California Arts Council]], was created in 1965. Its fifteen appointed members act in an advisory capacity to the board of supervisors, in promoting the arts. The [[Oakland Museum of California]] has a substantial collection of California art works and historical artifacts.

==Sports==
The following sports teams play in Alameda County:
{| class="wikitable"
|-
!Club
!Sport
!Founded
!League
!Venue
|-
|[[California Golden Bears]]
|[[NCAA]]
|1868
|[[NCAA]]: [[Atlantic Coast Conference|ACC]]
|[[California Memorial Stadium]] (Football), [[Haas Pavilion]] (Basketball), [[Evans Diamond]] (Baseball)
|-
|[[East Bay FC Stompers]]
|[[Association football|Soccer]]
|2012 (in [[San Francisco]] from 2012 to 2015) 
|[[National Premier Soccer League]]: Golden Gate Conference
|[[Pioneer Stadium]]
|-
|[[Oakland Roots]]
|[[Soccer]]
|2018
|[[USL Championship]]
|[[Pioneer Stadium]]
|}

== Events ==
The annual county fair is held at the [[Alameda County Fairgrounds]] in [[Pleasanton, California|Pleasanton]]. The fair runs for four weekends from June to July. Attractions include horse racing, carnival rides, [[4-H]] exhibits, and live bands.

== Parks and recreation ==
There are more than 350 parks located within the county.<ref>[http://california.hometownlocator.com/features/cultural,class,park,scfips,06001.cfm Alameda County California Parks]. California.hometownlocator.com. Retrieved on July 15, 2013.</ref> The [[East Bay Regional Park District]] operates within Alameda and neighboring Contra Costa County, with numerous parks within the county, including [[Tilden Regional Park]], [[Redwood Regional Park]], [[Anthony Chabot Regional Park]], [[Coyote Hills Regional Park]], [[Ardenwood Historic Farm]], [[Pleasanton Ridge Regional Park]] and [[Vargas Plateau Regional Park]]. [[Eastshore State Park]] is located partially along the bay shore of northern Alameda County. The [[San Francisco Bay Trail]], a project of the [[Association of Bay Area Governments]], will run along the bay shore of the county.<ref>[https://archive.today/20120701154134/http://baytrail.abag.ca.gov/maps.html San Francisco Baytrail]. Baytrail.abag.ca.gov. Retrieved on July 15, 2013.</ref> The [[Hayward Area Recreation and Park District]] is the largest special park district in California.

==Transportation==

===Major highways===
<!-- Do not add any county routes or highway names here without discussion. -->
* {{jct|state=CA|I|80}}
* {{jct|state=CA|I|205}}
* {{jct|state=CA|I|238|SR|238}}
* {{jct|state=CA|I|580}}
* {{jct|state=CA|I|680}}
* {{jct|state=CA|I|880}}
* {{jct|state=CA|I|980}}
* {{jct|state=CA|SR|13}}
* {{jct|state=CA|SR|24}}
* {{jct|state=CA|SR|61}}
* {{jct|state=CA|SR|77}}
* {{jct|state=CA|SR|84}}
* {{jct|state=CA|SR|92}}
* {{jct|state=CA|SR|123|location1=former [[U.S. Route 40 in California|US&nbsp;40]]}}
* {{jct|state=CA|SR|185}}
* {{jct|state=CA|SR|262}}

===Mass transit===
====Rail====
* [[Altamont Corridor Express|Altamont Corridor Express (ACE)]] – commuter rail using existing railroad tracks; primarily brings commuters from San Joaquin County to Santa Clara County
* [[Amtrak]]
** ''[[California Zephyr]]'' – intercity train route running between Emeryville and [[Chicago]].
** ''[[Capitol Corridor]]'' – commuter rail using existing railroad tracks, extending from San Jose to Sacramento, running through western Alameda County
** ''[[Coast Starlight]]'' – intercity train route running between Los Angeles and Seattle via Oakland and Emeryville
** ''[[Gold Runner]]'' – Amtrak route between Oakland and Bakersfield through Fresno and the Central Valley
* [[Bay Area Rapid Transit|Bay Area Rapid Transit (BART)]] – rapid transit commuter rail centered on northwest Oakland, primarily serving commuters to downtown San Francisco and downtown Oakland
* ''[[Valley Link]]'' – planned commuter rail running between the [[Tri-Valley]] and [[San Joaquin County, California|San Joaquin County]] (expected to commence in 2028)

====Bus====
* [[AC Transit]] – local [[bus]] system in western Alameda County and west Contra Costa County, with additional service across the three bridges from Alameda County to downtown San Francisco, San Mateo, and Palo Alto
* [[WHEELS (California)|WHEELS]] – bus system in the cities of southeastern Alameda County
* [[Union City Transit]] – local city bus service within [[Union City, California|Union City]] in addition to AC Transit
* [[Emery-Go-Round]] – free bus service in [[Emeryville, California|Emeryville]]
* [[Dumbarton Express]] – additional service across the [[Dumbarton Bridge (California)|Dumbarton Bridge]] between Fremont and Palo Alto
* [[Santa Clara Valley Transportation Authority|Santa Clara Valley Transportation Authority (VTA)]] – commuter service between southern Alameda county and job centers in the Silicon Valley

====Ferry====
* [[Alameda / Oakland Ferry]] and [[Harbor Bay Ferry]] – connect Oakland, Alameda, and Bay Farm Island with downtown San Francisco

===Airports===
The main airport is the [[Oakland San Francisco Bay Airport]], with two [[general aviation]] airports, the [[Hayward Executive Airport]] and [[Livermore Municipal Airport]].

==Services==
[[Alameda Health System]] operates the public health system in Alameda County. It operates five hospitals ([[Alameda Hospital]], Fairmont Hospital, [[Highland Hospital (Oakland, California)|Highland Hospital]], John George Psychiatric Hospital, and San Leandro Hospital), and four primary care medical clinics (called ambulatory wellness centers) within the county.

The [[Alameda County Community Food Bank]] nonprofit provides [[food bank]] resources to residents. The Family Emergency Shelter Coalition coordinates services for homeless families.

== Landmarks ==
Alameda County has eight [[National Historic Landmarks]]: [[Joaquin Miller House|The Abbey, Joaquin Miller House]], [[First Church of Christ, Scientist (Berkeley, California)|First Church of Christ, Scientist]], [[USS Hornet (CV-12)|USS ''Hornet'' (CVS-12) (aircraft carrier)]], [[Lake Merritt|Lake Merritt Wild Duck Refuge]], [[Lightship WAL-605 Relief|Lightship WAL-605, ''Relief'']], [[Paramount Theater (Oakland, California)|Paramount Theatre]], [[USS Potomac (AG-25)|''Potomac'' (Presidential yacht)]], and [[Gilman Hall|Room 307, Gilman Hall, University of California]]. The county has a large [[National Register of Historic Places listings in Alameda County, California|number of National Historic Places]], as well as [[California Historical Landmarks in Alameda County, California|a number of California Historical Landmarks]].

==Sister counties==
Alameda has two [[sister city|sister county]]: [[Taoyuan City|Taoyuan County, Taiwan]] (now Taoyuan City) and [[Zhongshan]] in [[China]].<ref>[http://www.acgov.org/Sister_Site/ Alameda – Taoyuan Sister County Association – Homepage]. Acgov.org. Retrieved on July 15, 2013.</ref>

==Communities==
[[File:Alameda County California Incorporated and Unincorporated areas annotated.svg |right|Cities and census designated places of Alameda County]]

===Cities===
{| class="wikitable sortable" style="margin:auto;"
|-
! No. <br />on Map
! City
! Year <br />incorporated
! Population, <br />2020<ref>{{cite web |title=U.S. Census Bureau QuickFacts: Alameda County, California |url=https://www.census.gov/quickfacts/fact/table/alamedacountycalifornia/POP010220 |website=United States Census Bureau |access-date=June 25, 2023}}</ref>
|-
| 1
| [[Alameda, California|Alameda]]
| 1854
| 78,280
|-
| 2
| [[Albany, California|Albany]]
| 1908
| 20,271
|-
| 3
| [[Berkeley, California|Berkeley]]
| 1878
| 124,321
|-
| 4
| [[Dublin, California|Dublin]]
| 1982
| 72,589
|-
| 5
| [[Emeryville, California|Emeryville]]
| 1896
| 12,905
|-
| 6
| [[Fremont, California|Fremont]]
| 1956
| 230,504
|-
| 7
| [[Hayward, California|Hayward]]
| 1876
| 162,954
|-
| 8
| [[Livermore, California|Livermore]]
| 1876
| 87,955
|-
| 9
| [[Newark, California|Newark]]
| 1955
| 47,529
|-
| 10
| [[Oakland, California|Oakland]] (county seat)
| 1852
| 440,646
|-
| 11
| [[Piedmont, California|Piedmont]]
| 1907
| 11,270
|-
| 12
| [[Pleasanton, California|Pleasanton]]
| 1894
| 79,871
|-
| 13
| [[San Leandro, California|San Leandro]]
| 1872
| 91,008
|-
| 14
| [[Union City, California|Union City]]
| 1959
| 70,143
|}

===Census-designated places===
<ol start="20">
<li>  [[Ashland, California|Ashland]]</li>
<li>  [[Castro Valley, California|Castro Valley]]</li>
<li>  [[Cherryland, California|Cherryland]]</li>
<li>  [[Fairview, California|Fairview]]</li>
<li>  [[San Lorenzo, California|San Lorenzo]]</li>
<li>  [[Sunol, California|Sunol]]</li>
</ol>

===Unincorporated communities===
{{Div col|colwidth=12em}}
* [[Altamont, California|Altamont]]
* [[Brightside, California|Brightside]]
* Carpenter
* [[Dougherty, Alameda County, California|Dougherty]]
* [[Dresser, California|Dresser]]
* [[East Pleasanton, California|East Pleasanton]]
* [[Hayward Acres, California|Hayward Acres]]
* [[Kilkare Woods, California|Kilkare Woods]]
* [[Komandorski Village, California|Komandorski Village]]
* [[Mendenhall Springs, California|Mendenhall Springs]]
* [[Midway, Alameda County, California|Midway]]
* [[Mountain House, Alameda County, California|Mountain House]]
* [[Mowry Landing, California|Mowry Landing]]
* [[San Ramon Village, California|San Ramon Village]]
* Scotts Corner
* [[Verona, California|Verona]]
{{div col end}}

=== Former townships ===
[[File:Map of Alameda County 1878 LARGE.jpg|thumb|right|300px|Map of Alameda County, 1878 (Six Townships)]]
* Oakland Township – the northern portion subsequently became the cities of Berkeley and Albany.
* Alameda Township – now essentially coterminous with the City of Alameda.
* Brooklyn Township – mostly contained within Oakland and Piedmont.
* [[Eden Township, Alameda County, California|Eden Township]] – partly incorporated into San Leandro and Hayward, the rest contains the communities of Castro Valley, San Lorenzo, and other unincorporated areas.
* [[Washington Township, Alameda County, California|Washington Township]] – contains Union City, Newark, [[Fremont, California|Fremont]], and small unincorporated areas nearby.
* [[Murray Township, Alameda County, California|Murray Township]] — Contains cities of Dublin, Pleasanton, and Livermore, and substantial unincorporated areas including Sunol.

===Population ranking===
The population ranking of the following table is based on the [[2020 United States census|2020 census]] of Alameda County.<ref>{{cite web|url=https://www.census.gov/2020census/|title = By Decade}}</ref>

'''†''' ''county seat''

{| class="wikitable sortable"
|-
!Rank
!City/Town/etc.
!Municipal type
!Population (2020 Census)

|- style="background:#fffacd;"
| 1
|'''†''' '''[[Oakland, California|Oakland]]'''
| City
| 440,646
|- style="background:#fffacd;"
| 2
|'''[[Fremont, California|Fremont]]'''
| City
| 230,504
|- style="background:#fffacd;"
| 3
|'''[[Hayward, California|Hayward]]'''
| City
| 162,954
|- style="background:#fffacd;"
| 4
|'''[[Berkeley, California|Berkeley]]'''
| City
| 124,321
|- style="background:#fffacd;"
| 5
|'''[[San Leandro, California|San Leandro]]'''
| City
| 91,008
|- style="background:#fffacd;"
| 6
|'''[[Livermore, California|Livermore]]'''
| City
| 87,955
|- style="background:#fffacd;"
| 7
|'''[[Pleasanton, California|Pleasanton]]'''
| City
| 79,871
|- style="background:#fffacd;"
| 8
|'''[[Alameda, California|Alameda]]'''
| City
| 78,280
|- style="background:#fffacd;"
| 9
|'''[[Dublin, California|Dublin]]'''
| City
| 72,589
|- style="background:#fffacd;"
| 10
|'''[[Union City, California|Union City]]'''
| City
| 70,143
|- style="background:honeyDew;"
| 11
|'''[[Castro Valley, California|Castro Valley]]'''
| CDP
| 66,441
|- style="background:#fffacd;"
| 12
|'''[[Newark, California|Newark]]'''
| City
| 47,529
|- style="background:honeyDew;"
| 13
|'''[[San Lorenzo, California|San Lorenzo]]'''
| CDP
| 29,581
|- style="background:honeyDew;"
| 14
|'''[[Ashland, California|Ashland]]'''
| CDP
| 23,823
|- style="background:#fffacd;"
| 15
|'''[[Albany, California|Albany]]'''
| City
| 20,271
|- style="background:honeyDew;"
| 16
|'''[[Cherryland, California|Cherryland]]'''
| CDP
| 15,808
|- style="background:#fffacd;"
| 17
|'''[[Emeryville, California|Emeryville]]'''
| City
| 12,905
|- style="background:honeyDew;"
| 18
|'''[[Fairview, California|Fairview]]'''
| CDP
| 11,341
|- style="background:#fffacd;"
| 19
|'''[[Piedmont, California|Piedmont]]'''
| City
| 11,270
|- style="background:honeyDew;"
| 20
|'''[[Sunol, California|Sunol]]'''
| CDP
| 922
|}

==See also==
* [[USS Alameda County|USS ''Alameda County'' (LST-32)]], the only US Naval vessel named after the county
* [[National Register of Historic Places listings in Alameda County, California]]
* [[Solar power in Alameda County]]
*[[List of counties in California]]

== Notes ==
{{Reflist|group=note}}

==References==
{{Reflist|30em}}

==External links==
{{Sister project links|auto=y}}
* {{Official website}}
* [http://www.acgov.org/board/map.pdf map of Alameda County with supervisorial district boundaries]
* [http://www.alamedacountyfair.com Alameda County Fairgrounds – Annual county fair June to July]
* [https://archive.org/details/Californ1958 A short film about Alameda County from 1958]
* [http://www.acgov.org/fire/ Alameda County Fire Department]; {{Webarchive|url=https://web.archive.org/web/20160329195026/http://acgov.org/fire/ |date=March 29, 2016 }}
* [http://www.acfdtraining.com Alameda County Fire Department Training Division]
* [https://localwiki.org/berkeley/Hiking Hiking trails in Alameda County, at the Berkeley Wiki website]

{{Geographic Location
|Centre = Alameda County, California
|North = [[Contra Costa County, California|Contra Costa County]]
|Northeast =
|East = [[San Joaquin County, California|San Joaquin County]]
|Southeast = [[Stanislaus County, California|Stanislaus County]]
|South = [[Santa Clara County, California|Santa Clara County]]
|Southwest =
|West = [[San Francisco County, California|San Francisco County]] and [[San Mateo County, California|San Mateo County]]
|Northwest =
}}
{{Cities of Alameda County, California}}
{{Alameda County, California topics}}
{{East Bay}}
{{SF Bay Area}}
{{California}}
{{Authority control}}

[[Category:Alameda County, California| ]]
[[Category:1853 establishments in California]]
[[Category:California counties]]
[[Category:Counties in the San Francisco Bay Area]]
[[Category:Majority-minority counties in California]]
[[Category:Populated places established in 1853]]