View source for International Alphabet of Sanskrit Transliteration

{{Short description|Transliteration scheme for Indic scripts}}
{{redirect|IAST|the security testing method|Interactive application security testing}}
{{Use dmy dates|date=August 2022}}
{{Use Indian English|date=May 2016}}
{{Infobox romanization
| engvar    = gb
| name      = International Alphabet of Sanskrit Transliteration
| altname   = IAST
| languages = [[Sanskrit]] and other [[Languages of South Asia|Indic Languages]]
| time      = 19th century–present
| romanised-from = [[Indic scripts]]
}}
{{Contains special characters|Indic}}

The '''International Alphabet of Sanskrit Transliteration''' ('''IAST''') is a [[transliteration]] scheme that allows the lossless [[romanisation]] of [[Brahmic family|Indic scripts]] as employed by [[Sanskrit]] and related Indic languages. It is based on a scheme that emerged during the 19th century from suggestions by [[Sir Charles Trevelyan, 1st Baronet|Charles Trevelyan]], [[William Jones (philologist)|William Jones]], [[Monier Monier-Williams]] and other scholars, and formalised by the Transliteration Committee of the Geneva [[International Congress of Orientalists|Oriental Congress]], in September 1894.<ref>{{Cite book|url=http://www.sanskrit-lexicon.uni-koeln.de/scans/MWScan/MWScanpdf/mw010033.pdf|title=A Sanskrit-English Dictionary|last=Monier-Williams|first=Monier|publisher=Clarendon Press|year=1899|location=Oxford|pages=xxx|author-link=Monier Monier-Williams}}</ref><ref name="10th">{{cite journal |title=Tenth International Congress of Orientalists, Held at Geneva |journal=The Journal of the Royal Asiatic Society of Great Britain and Ireland |date=1895 |pages=879–892 |jstor=25207765 }}</ref> IAST makes it possible for the reader to read the Indic text unambiguously, exactly as if it were in the original Indic script. It is this faithfulness to the original scripts that accounts for its continuing popularity amongst scholars.

==Usage==
Scholars commonly use IAST in publications that cite textual material in Sanskrit, [[Pāḷi]] and other classical Indian languages.

IAST is also used for major e-text repositories such as SARIT, Muktabodha, GRETIL, and sanskritdocuments.org.

The IAST scheme is the most common system used for more than a century in scholarly books and journals on classical Indian studies,  though  often with some minor variations, such as common usage of ''ṃ'' instead of ṁ (and occasional usage of ''r̥'' instead of ṛ, especially in materials where the Devanagari letter ड़, used in Hindi, needs to be distinguished). More recently, the [[ISO 15919]] standard for transliterating Indic scripts emerged in 2001 from the standards and library worlds. For the most part, ISO 15919 follows the IAST scheme, departing from it only in minor ways (e.g., ḷ/l̥ and ṛ/r̥), the most notable being ISO 15919 ē, ō representing what IAST translates as e, o which in the ISO denote short vowels (a practice commonly established among scholars in [[Dravidian studies|Dravidian]] studies—see comparison below.

The Indian [[National Library at Kolkata romanization]], intended for the romanisation of all [[Brahmic family|Indic scripts]], is an extension of IAST.

==History==
The Tenth International Congress of Orientalists, held at Geneva on 10 September 1894, adopted the following notations:<ref name="10th"/><ref>{{cite web |url=https://archive.org/details/transliterationr00roya/page/4/mode/2up | title = Transliteration Report| date = 1896}}</ref>
[[File:Report of Transliteration Commitee from Pg 887.png|275px|thumb|Table from the Report of Transliteration Committee, Pg 887]]
{| class=wikitable
|-
!
| a || ā || i || ī || u || ū || ṛ || ṝ || ḷ || l̤ || e || ai || o || au
|-
!
| k || kh || g || gh || ṅ
|-
!
| c || ch || j || jh || ñ
|-
!
| ṭ || ṭh || ḍ || ḍh || ṇ
|-
!
| t || th || d || dh || n
|-
!
| p || ph || b || bh || m 
|-
!
| y || r || l || v || ś || ṣ || s || h || ḻ ||ṁ || m̐
|-
! visarga
| ḥ
|-
! jihvāmūlīya
| ẖ
|-
! upadhmānīya
| ḫ
|}

For the short e and o, the Committee also recommended the use of ĕ and ŏ, respectively.

==Inventory and conventions==
The IAST letters are listed with their [[Devanagari]] equivalents and phonetic values in [[International Phonetic Alphabet|IPA]], valid for [[Sanskrit]], [[Hindi]] and other modern languages that use Devanagari script, but some phonological changes have occurred:

{| class="wikitable"
|+ Vowels and codas
!Devanāgarī
!colspan=2|Transcription
!IPA for Sanskrit pronunciation
!Category
|-
|अ
|a
|A
|[[Near-open central vowel|ɐ]]
|rowspan=6|[[monophthongs]]
|-
|आ
|ā
|Ā
|[[Open front unrounded vowel|aː]]
|-
|इ
|i
|I
|[[Near-close near-front unrounded vowel|ɪ]]
|-
|ई
|ī
|Ī
|[[Close front unrounded vowel|iː]]
|-
|उ
|u
|U
|[[Near-close near-back rounded vowel|ʊ]]
|-
|ऊ
|ū
|Ū
|[[Close back rounded vowel|uː]]
|-
|ऋ
|ṛ
|Ṛ
|[[Syllabic consonant|r̩]]
|rowspan=4|[[syllabic consonant|syllabic]] [[liquid consonant|liquid]]s
|-
|ॠ
|ṝ
|Ṝ
|[[Syllabic consonant|r̩ː]]
|-
|ऌ
|ḷ
|Ḷ
|[[Syllabic consonant|l̩]]
|-
|ॡ
|ḹ
|Ḹ
|[[Syllabic consonant|l̩ː]]
|-
|ए
|e
|E
|[[Close-mid front unrounded vowel|e]]
|rowspan=4|[[diphthong]]s
|-
|ऐ
|ai
|Ai
|ɐi̯
|-
|ओ
|o
|O
|[[Close-mid back rounded vowel|o]]
|-
|औ
|au
|Au
|ɐu̯
|-
|ं
|ṁ
|Ṁ
|
|[[anusvara]]
|-
|ः
|ḥ
|Ḥ
|
|[[visarga]]
|-
|ँ
|m̐
|M̐
|
|[[chandrabindu]]<ref>See, now, the [[Talk:International Alphabet of Sanskrit Transliteration#Candrabindu|Talk page]], where m̐ is recommended.</ref>
|-
|ऽ
|'
|
|
|[[avagraha]]
|}

{| class="wikitable"
|+ Consonants
|-
![[velar consonant|velars]]
![[palatal consonant|palatals]]
![[retroflex consonant|retroflexes]]
![[dental consonant|dentals]]
![[labial consonant|labials]]
!Category
|-
|क <br> k&nbsp;&nbsp;K
|च <br> c&nbsp;&nbsp;C
|ट <br> ṭ&nbsp;&nbsp;Ṭ
|त <br> t&nbsp;&nbsp;T
|प <br> p&nbsp;&nbsp;P
| [[tenuis consonant|tenuis]] stops
|- 
|ख <br> kh&nbsp;&nbsp;Kh
|छ <br> ch&nbsp;&nbsp;Ch
|ठ <br> ṭh&nbsp;&nbsp;Ṭh
|थ <br> th&nbsp;&nbsp;Th
|फ <br> ph&nbsp;&nbsp;Ph
| [[Aspiration (phonetics)|aspirated]] stops
|- 
|ग <br> g&nbsp;&nbsp;G
|ज <br> j&nbsp;&nbsp;J
|ड <br> ḍ&nbsp;&nbsp;Ḍ
|द <br> d&nbsp;&nbsp;D
|ब <br> b&nbsp;&nbsp;B
|[[voiced consonant|voiced]] stops
|-
|घ <br> gh&nbsp;&nbsp;Gh
|झ <br> jh&nbsp;&nbsp;Jh
|ढ <br> ḍh&nbsp;&nbsp;Ḍh
|ध <br> dh&nbsp;&nbsp;Dh
|भ <br> bh&nbsp;&nbsp;Bh
|[[breathy-voiced]] stops
|- 
|ङ <br> ṅ&nbsp;&nbsp;Ṅ
|ञ <br> ñ&nbsp;&nbsp;Ñ
|ण <br> ṇ&nbsp;&nbsp;Ṇ
|न <br> n&nbsp;&nbsp;N
|म <br> m&nbsp;&nbsp;M
|[[nasal stop]]s
|- 
|ह <br> h&nbsp;&nbsp;H<sup>*</sup>
|य <br> y&nbsp;&nbsp;Y
|र <br> r&nbsp;&nbsp;R
|ल <br> l&nbsp;&nbsp;L
|व <br> v&nbsp;&nbsp;V
|[[approximant]]s
|- 
| &nbsp; 
|श <br> ś&nbsp;&nbsp;Ś
|ष <br> ṣ&nbsp;&nbsp;Ṣ
|स <br> s&nbsp;&nbsp;S
| &nbsp; 
|[[sibilant]]s
|- 
|&nbsp; 
|&nbsp; 
|ळ <br> ḻ&nbsp;&nbsp;Ḻ
|&nbsp; 
|&nbsp; 
|[[approximant]]s ([[Vedic Sanskrit|Vedic]])<ref name="10th"/>

|}
<nowiki>*</nowiki> ''H'' is actually [[glottal consonant|glottal]], not [[velar consonant|velar]].

In practice, the letter ṁ is commonly substituted by ṃ. 

Some letters are modified with [[diacritic]]s: Long vowels are marked with an [[overline]] (often called a [[macron (diacritic)|macron]]). Vocalic (syllabic) consonants, retroflexes and ṣ ({{IPA|/[[ʂ]]/}} in Sanskrit, [ʃ] in Hindi) have an [[underdot]]. Two letters have an overdot: ṁ and ṅ ({{IPA|/ŋ/}}). One has an [[acute accent]]: ś ({{IPA|/[[ɕ]]}} in Sanskrit, {{IPA|/ʃ/}} in Hindi). One letter has a line below: ḻ ({{IPA|/[[ɭ]]/}}) (the intervocalic allophone of ḍ in Vedic Sanskrit).

Unlike [[ASCII]]-only romanisations such as [[ITRANS]] or [[Harvard-Kyoto]], the diacritics used for IAST allow capitalisation of proper names. The capital variants of letters never occurring word-initially ({{IAST|Ṁ Ṇ Ṅ Ñ Ṝ Ḹ}}) are useful only when writing in all-caps and  in [[Pāṇini]] contexts for which the convention is to typeset the ''[[Aṣṭādhyāyī|IT]]'' sounds as capital letters.

==Comparison with ISO 15919==
For the most part, IAST is a subset of [[ISO 15919]] that merges the retroflex (underdotted) liquids with the vocalic ones ([[ring (diacritic)#Ring below|ringed below]]) and the short [[close-mid vowel]]s with the long ones. The following seven exceptions are from the ISO standard accommodating an extended repertoire of symbols to allow transliteration of [[Devanāgarī]] and other [[Indic scripts]] as used for languages other than Sanskrit.

{| class="wikitable"
|-
!Devanāgarī 
!IAST 
!ISO 15919
!Comment
|-&nbsp;
||{{lang|hi|ए / े}}
||e
||ē (e)
||ISO ''e'' generally represents short {{lang|hi|ऎ / ॆ}}, but optionally represents long {{lang|hi|ए / े}} in the Devanagari, Bengali, Gurmukhi, Gujarati, and Odia scripts.
|-
||{{lang|hi|ओ / ो}}
||o
||ō (o)
||ISO ''o'' generally represents short {{lang|hi|ऒ / ॆ}}, but optionally represents long {{lang|hi|ओ / ो}} in the Devanagari, Bengali, Gurmukhi, Gujarati, and Odia scripts.
|-
||{{lang|hi|ऎ / ॆ}}
||ĕ
||e
||ISO ''e'' generally represents short {{lang|hi|ऎ / ॆ}}, but optionally represents long {{lang|hi|ए / े}} in the Devanagari, Bengali, Gurmukhi, Gujarati, and Odia scripts. The IAST ''ĕ'' represents short {{lang|hi|ऎ / ॆ}}.
|-
||{{lang|hi|ऒ / ॆ}}
||ŏ
||o
||ISO ''o'' generally represents short {{lang|hi|ऒ / ॆ}}, but optionally represents long {{lang|hi|ओ / ो}} in the Devanagari, Bengali, Gurmukhi, Gujarati, and Odia scripts. The IAST ''ŏ'' represents short {{lang|hi|ऒ / ॆ}}.
|-
||{{lang|hi|ऋ / ृ}}
||ṛ
||r̥
||ISO ''ṛ''  represents ड़ {{IPAslink|ɽ}}.
|-
||{{lang|hi|ॠ / ॄ}}
||ṝ
||r̥̄
||for consistency with ''r̥''.
|-
||{{lang|hi|ऌ / ॢ}}
||ḷ
||l̥
||ISO ''ḷ''  represents ळ {{IPAslink|𝼈}}. 
|-
||{{lang|hi|ॡ / ॣ}}
||ḹ
||l̥̄
||for consistency with ''l̥''.
|-
||ळ
||ḻ
||ḷ
||Used in Vedic Sanskrit only and not found in the Classical variant
|}

== Computer input by alternative keyboard layout ==
The most convenient method of inputting romanized Sanskrit is by setting up an alternative [[keyboard layout]]. This allows one to hold a modifier key to type letters with diacritical marks.  For example, {{keypress|alt|a}} = ā. How this is set up varies by operating system.

[[Unix|Linux/Unix]] and BSD desktop environment users can set up custom keyboard layouts and switch them by clicking a flag icon in the menu bar.

[[macOS]] users can use the pre-installed US International keyboard, or install Toshiya Unebe's Easy Unicode keyboard layout.

[[Microsoft Windows]] users can change keyboard layouts and set up additional custom keyboard mappings for IAST. This Pali keyboard installer<ref>{{Cite web|url=http://fsnow.com/pali/keyboard/|title=Pali Keyboard|website=fsnow.com|access-date=21 October 2019}}</ref> made by Microsoft Keyboard Layout Creator (MSKLC) supports IAST (works on Microsoft Windows up to at least version 10, can use Alt button on the right side of the keyboard instead of Ctrl+Alt combination).

[[Android (operating system)|Android]] keyboard called "Sanskrit (Latin)" offers IAST and ISO characters - these can be entered by holding the key for the corresponding letters without diacritic: e.g. holding "s" calls a selection between ś and ṣ.

== Computer input by selection from a screen==
{{further|Unicode input#Selection from a screen}}
[[File:Gucharmap screenshot.png|thumb|300px|Applet for character selection]]

Many systems provide a way to select Unicode characters visually. [[ISO/IEC 14755]] refers to this as a ''screen-selection entry method''.

[[Microsoft Windows]] has provided a Unicode version of the Character Map program (find it by hitting {{keypress|Win|R}} then type <code>charmap</code> then hit {{keypress|Enter}}) since version NT 4.0&nbsp;– appearing in the consumer edition since XP. This is limited to characters in the [[Basic Multilingual Plane]] (BMP). Characters are searchable by Unicode character name, and the table can be limited to a particular code block. More advanced third-party tools of the same type are also available (a notable [[freeware]] example is [[Andrew West (linguist)#BabelMap|BabelMap]]).

[[Mac OS X|macOS]] provides a "character palette" with much the same functionality, along with searching by related characters, glyph tables in a font, etc. It can be [https://web.archive.org/web/20110109234035/http://www.apple.com/pro/techniques/glyphspalette/ enabled] in the input menu in the menu bar under System Preferences → International → Input Menu (or System Preferences → Language and Text → Input Sources) or can be viewed under Edit → Emoji & Symbols in many programs.

Equivalent tools&nbsp;– such as [[gucharmap]] ([[GNOME]]) or [[List of KDE applications|kcharselect]] ([[KDE]])&nbsp;– exist on most Linux desktop environments.

Users of SCIM on Linux based platforms can also have the opportunity to install and use the sa-itrans-iast input handler which provides complete support for the ISO 15919 standard for the romanization of Indic languages as part of the m17n library.

Or user can use some Unicode characters in Latin-1 Supplement, Latin Extended-A, Latin Extended Additional and Combining Diarcritical Marks block to write IAST.

== Font support ==
{{expand section|date=September 2016}}

Only certain [[font]]s support all the Latin [[Unicode]] characters essential for the transliteration of Indic scripts according to the IAST and ISO 15919 standards.

For example, the [[Arial]], [[Tahoma (typeface)|Tahoma]] and [[Times New Roman]] font packages that come with [[Microsoft Office 2007]] and later versions also support precomposed Unicode characters like ''ī''. Google's [[Noto]] font covers IAST. 

Many other text fonts commonly used for book production may be lacking in support for one or more characters from this block. Accordingly, many academics working in the area of Sanskrit studies make use of free OpenType fonts such as FreeSerif or [[Gentium]], both of which have complete support for the full repertoire of conjoined diacritics in the IAST character set. Released under the [[GNU FreeFont]] or [[SIL Open Font License]], respectively, such  fonts may be freely shared and do not require the person reading or editing a document to purchase proprietary software to make use of its  associated fonts.

==See also==
{{col div|colwidth=30em}}
* [[Devanagari transliteration]]
* [[Āryabhaṭa numeration]]
* [[Hunterian transliteration]]
* [[Harvard-Kyoto]]
* [[ITRANS]]
* [[ISO 15919]]
* [[National Library at Kolkata romanisation]]
* [[Shiva Sutras]]
* [[Template:IAST]]
{{colend}}

==References==
{{reflist}}

==External links ==
* {{Cite web |url=http://shashir.autodidactus.org/shashir_umich/sanskrit_transcription.html|title=Shashir's Notes: Modern Transcription of Sanskrit|last=Reddy|first=Shashir}}
* {{Cite web |url=https://www.lexilogos.com/keyboard/index.htm|title=Mutlilingual keyboard}}

{{DEFAULTSORT:International Alphabet Of Sanskrit Transliteration}}
[[Category:Hindustani orthography]]
[[Category:Romanization of Brahmic]]
[[Category:Sanskrit transliteration]]
[[Category:Encodings]]