The full standard ISO 11940-2:2007 includes pronunciation rules and conversion tables of Thai consonants and vowels.
The standard ISO 11940 (to be renamed 11940-1) defines a strict and reversible transliteration of Thai orthography into Latin characters, by means of a host of diacritics.
Prominent features of ISO 11940-2 include: Transcription is according to pronunciation, not Thai orthography, especially notable in final consonants.
In each cell below, the first line indicates International Phonetic Alphabet (IPA), the second indicates the Thai characters in initial position (several letters appearing in the same box have identical pronunciation).
The basic vowels of the Thai language, from front to back and close to open, are given in the following table.
Thai vowels come in long-short pairs, forming distinct phonemes, but ISO 11940-2 represents both by the same symbol.