The International Alphabet of Sanskrit Transliteration (IAST) is a transliteration scheme that allows a lossless romanization of Indic scripts as employed by the Sanskrit language. It is also used to romanize Pāḷi, Prākṛta and Apabhraṁśa.


IAST is especially used for books dealing with ancient Sanskrit and Pāḷi topics related to Indian religions. The script is, however, insufficient to represent both Sanskrit and Pāḷi on the same page properly because the , a vowel in Sanskrit, is the retroflexive consonant in Pāḷi. Here it is better to follow Unicode and ISO 15919, which is in any case a more comprehensive scheme.

IAST is based on a standard established by the International Congress of Orientalists at Geneva in 1894.[1][2] It allows a lossless transliteration of Devanāgarī (and other Indic scripts, such as Śāradā script); and, as such, it represents not only the phonemes of Sanskrit, but allows essentially phonetic transcription. E.g., Visarga is an allophone of word-final r and s.

The National Library at Kolkata romanization, intended for the romanization of all Indic scripts, is an extension of IAST.

Sign inventory and conventions

The sign inventory of IAST (both small and capital letters) shown with Devanāgarī equivalents and phonetic values in IPA, is as follows (valid for Sanskrit; for Hindi and other modern languages that use Devanagari script, some phonological changes have occurred):

Category Devanāgarī Transcription Lower case Upper case
vowels [ɐ] a A
[ɑː] ā Ā
[i] i I
[iː] ī Ī
[u] u U
[uː] ū Ū
diphthongs [eː] e E
[aːi] ai Ai
[oː] o O
[aːu] au Au
anusvara अं [ⁿ]
visarga अः [h]
velars palatals retroflexes dentals labials
k  K
c  C
ṭ  Ṭ
t  T
p  P
tenuis plosives
kh  Kh
ch  Ch
ṭh  Ṭh
th  Th
ph  Ph
aspirated plosives
g  G
j  J
ḍ  Ḍ
d  D
b  B
voiced plosives
gh  Gh
jh  Jh
ḍh  Ḍh
dh  Dh
bh  Bh
breathy-voiced plosives
ṅ  Ṅ
ñ  Ñ
ṇ  Ṇ
n  N
m  M
nasal stops
y  Y
r  R
l  L
v  V
ś  Ś
ṣ  Ṣ
s  S
h  H
        voiced fricative

Unlike ASCII-only romanizations such as ITRANS or Harvard-Kyoto, the diacritics used for IAST allow capitalization of proper names. The capital variants of letters which never occur word-initially (Ṇ Ṅ Ñ Ṝ) are useful only in Pāṇini contexts, where the convention is to typeset the IT sounds as capital letters.

Comparison with ISO 15919

For the most part, IAST is a subset of ISO 15919. The following five exceptions are due to 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.

Devanāgarī IAST ISO 15919 Comment
ए/ े e ē ISO e represents ऎ/ ॆ.
ओ/ो o ō ISO o represents ऒ/ॊ.
 ं ISO represents Gurmukhi Tippi  ੰ.
ऋ/ ृ ISO represents ड़ /ɽ/.
ॠ/ ॄ r̥̄ for consistency with .

See also


External links

  • Typing a macron - page from Penn State University about typing with accents
  • Devanagari online converter (Transliteration tool)