Replica of the Ramkhamhaeng inscription, the oldest inscription using Thai script
Replica of the Ramkhamhaeng inscription, the oldest inscription using Thai script

The Thai alphabet is probably derived from the Old Khmer script (อักขระเขมร), which is a southern Brahmic script of the Indic family. According to tradition it was created in 1283 by King Ramkhamhaeng the Great (พ่อขุนรามคำแหงมหาราช).

Alphabet listing

You will need a Unicode-capable browser and font that contains the Thai alphabet to view the Thai letters below.


There are 44 consonants representing 21 distinct consonant sounds. Duplicate consonants represent different Sanskrit and Pali consonants pronounced identically in Thai. Their continued use is necessary to differentiate among unrelated loan-words which are Thai homophones. The consonants are divided into three classes - low, middle and high - which determine the tone of the following vowel. There are in addition four consonant-vowel combination characters not included in the tally of 44.

To aid learning, each consonant is traditionally associated with a Thai word that either starts with the same sound, or features it prominently. For example, the name of the letter ข is kho khai (ข ไข่), in which kho is the sound it represents, and khai (ไข่) is a word which starts with the same sound and means "egg".

Two of the consonants (kho khuat and kho khon) aren't used in written Thai anymore. Some say that when the first Thai typewriter was developed by Edwin Hunter McFarland in 1892, there was simply no space for all characters, thus two had to be left out.

Equivalents for Romanization are shown in the table below. Many consonants are pronounced differently at the beginning and at the end of a syllable. The entries in columns initial and final indicate the pronunciation for that consonant in the corresponding positions in a syllable. Where the entry is "-", the consonant may not be used to close a syllable. Where a combination of consonants ends a written syllable, only the first is pronounced; possible closing consonant sounds are limited to 'k', 'm', 'n', 'ng', 'p' and 't'.

Although an official standard for Romanisation is defined by the Royal Thai Institute, many publications use different Romanisation systems. In daily practice, a bewildering variety of Romanisations are used, making it difficult to know how to pronounce a word, or to judge if two words (e.g. on a map and a street sign) are actually the same. For more precise information, an equivalent from the International Phonetic Alphabet (IPA) is given as well.

Each consonant is assigned to a "class" (Low, Middle, High), which plays a role in determining the tone with which the syllable is pronounced.

Symbol Name Royal Thai IPA Class
    Initial Final Initial Final Class
ko kai (chicken) k k k k M
kho khai (egg) kh k k H
kho khuat (bottle) [obsolete] kh k k H
kho khwai (water buffalo) kh k k L
kho khon (person) [obsolete] kh k k L
kho ra-khang (bell) kh k k L
ngo ngu (snake) ng ng ŋ ŋ L
cho chan (plate) ch t t M
cho ching (cymbals) ch - tɕʰ - H
cho chang (elephant) ch t tɕʰ t L
so so (chain) s t s t L
cho choe (bush) ch - tɕʰ - L
yo ying (woman) y n j n L
do cha-da (headdress) d t d t M
to pa-tak (goad) t t t t M
tho san-than (base) th t t H
tho nangmon-tho (dancer) th t t L
tho phu-thao (old person) th t t L
no nen (novice monk) n n n n L
do dek (child) d t d t M
to tao (turtle) t t t t M
tho thung (sack) th t t H
tho thahan (soldier) th t t L
tho thong (flag) th t t L
no nu (mouse) n n n n L
bo baimai (leaf) b p b p M
po plaa (fish) p p p p M
pho phueng (bee) ph - - H
fo fa (lid) f - f - H
pho phan (tray) ph p p L
fo fan (teeth) f p f p L
pho sam-phao (sailboat) ph p p L
mo ma (horse) m m m m L
yo yak (ogre) y y j j L
ro ruea (boat) r n r n L
ro rue (short) * rue - - -
ฤๅ ro rue (long) * rue - rɯː - -
lo ling (monkey) l n l n L
lo lue (short) * lue - - -
ฦๅ lo lue (long) * lue - lɯː - -
wo waen (ring) w w w w L
so sala (pavilion) s t s t H
so rue-si (hermit) s t s t H
so suea (tiger) s t s t H
ho hip (chest) h - h - H
lo chu-la (kite) l n l n L
o ang (basin) ** - ʔ - M
ho nok-huk (owl) h - h - L
  • Consonant-vowel combination characters, not members of any group.
    • อ is a special case in that at the beginning of a word it is used as a silent initial for syllables that start with a vowel (all vowels are written relative to a consonant — see below).


Thai vowel sounds and diphthongs are written using a mixture of vowel symbols, consonants, and combinations of vowel symbols. Each vowel is shown in its correct position relative to an initial consonant (indicated by a dash "–") and sometimes a final consonant as well (second dash). Note that vowels can go above, below, left of or right of the consonant, or combinations of these places. If a vowel has parts before and after the initial consonant, and the syllable starts with a consonant cluster, the split will go around the whole cluster.

The pronunciation is indicated by the International Phonetic Alphabet and the Romanisation according to the Royal Thai Institute as well as several variant Romanisations often encountered. A very approximate equivalent in Northeastern US English is given.

Symbol Name IPA Royal Variants Sound
implied a a a u u in "nut"
– – implied o o o   oa in "boat"
–รร– ro han * ɑ a u u in "nut"
–ว– wo waen * ua ua uar ewe in "newer"
–วย sara uai uɛj uai   uoy in "buoy"
–อ sara o ɔː o or, aw, ow aw in "saw"
–อย sara oi ɔːj oi oy oy in "boy"
–ะ sara a a u u in "nut"
–ั – mai han-akat ɑ a u u in "nut"
–ัย sara ai ɑj ai   i in "hi"
–ัว sara ua ua ua ewer ewe in "newer"
–ัวะ sara ua uaʔ ua ewer ewe in "sewer"
–า sara a a ar, aa a in "father"
–าย sara ai aːj ai aai, aay ye in "bye"
–าว sara ao aːw ao ow in "now"
–ำ sara am ɑm am um um in "sum"
–ิ sara i i i   y in "greedy"
–ิว sara iu iw iu   ew in "new"
–ี sara i i ee, ii, y ee in "see"
–ึ sara ue ɯ ue eu, uh u in French "du" (short)
–ื sara ue ɯː ue eu u in French "dur" (long)
–ุ sara u u u oo oo in "look"
–ู sara u u oo, uu ue in "sue"
เ– sara e e ay, a, ae, ai a in "lame"
เ–็ – sara e e e   e in "neck"
เ–ะ sara e e eh e in "neck"
เ–ย sara oei ɤːj oei   u in "burn" + y in "boy"
เ–อ sara oe ɤː oe ur, eu, u u in "burn"
เ–อะ sara oe ɤʔ oe eu, u e in "the"
เ–ิ – sara oe ɤ oe eu, u e in "the"
เ–ว sara eo eːw eo eu, u ai + ow in "rainbow"
เ–า sara ao aw ao aw, ow ow in "cow"
เ–าะ sara o ɔʔ o orh, oh, or o in "not"
เ–ีย sara ia iːa ia ear, ere ea in "ear"
เ–ียะ sara ia iaʔ ia iah, ear ea in "ear" with
glottal stop
เ–ียว sara iao io iao iow io in "trio"
เ–ือ sara uea ɯːa uea eua, ua ure in "pure"
เ–ือะ sara uea ɯaʔ uea eua, ua ure in "pure"
แ– sara ae ɛː ae a, e a in "ham"
แ–ะ sara ae ɛʔ ae aeh, a a in "at"
แ–็ – sara ae ɛ ae aeh, a a in "at"
แ–ว sara aeo ɛːw aeo eo a in "ham" + ow in "low"
โ– sara o o or, oh o in "go"
โ–ะ sara o o oh o in "poke"
ใ– sara ai mai muan ɑj ai ay, y i in "I"
ไ– sara ai mai malai ɑj ai ay, y i in "I"
  • vowels or diphthongs written with consonant symbols


Each mark is shown in its correct location relative to the consonant kor kai. The names of the tones are derived from the numbers one, two, three and four in an Indic language.

Symbol Name Meaning
ก่ mai ek first tone mark
ก้ mai tho second tone mark
ก๊ mai tri third tone mark
ก๋ mai jattawa fourth tone mark
ก็ mai taikhu shortens vowel
ก์ mai thantakhat, karan indicates silent letter

Other symbols

Symbol Name Meaning
paiyaan noi preceding word is abbreviated
ฯลฯ paiyaan yai etc.
mai yamok preceding word or phrase is repeated

Thai in computing

TIS-620 is the best-established character set and character encoding for the Thai alphabet. TIS-620 has been adopted verbatim in the Unicode range for Thai, U+0E00 ... U+0E7F.

    0 1 2 3 4 5 6 7 8 9 A B C D E F
E30    ั  ิ  ี  ึ  ื  ุ  ู  ฺ ฿
E40    ็  ่  ้  ๊  ๋  ์  ํ  ๎
E70   ๿