The Thai writing system
Thai has no spaces between words and no capital letters — but it is fully phonetic once you know the rules. Reading comes down to three things: the consonant's class, the vowel, and any tone mark. Those decide the tone.
Prefer prose? Read the alphabet guide, consonants, and vowels.
Drill itHow a word breaks down
Every syllable is an initial consonant, a vowel placed around it, and (sometimes) a tone mark. A silent ห or อ in front can change the class the syllable reads as.
Consonants by class
The 44 consonants fall into three tone classes. The class is half of the tone equation — the same vowel and mark give different tones depending on it.
Mid class · 9
High class · 11
Low class · 24
Vowels
Vowels sit before, after, above, below, or around the consonant (◌ marks the consonant slot). Length is phonemic — short vs long can change both meaning and tone.
Tone marks
Four marks sit above the consonant. Crucially, a mark does not name its own tone — what it produces depends on the consonant class (see the table below).
The tone rules
Class × syllable (live/dead) × vowel length × tone mark → the tone. This is the whole game. Note the low-class quirk: ◌่ gives falling and ◌้ gives high.
| Class | Live | Dead · short | Dead · long | ◌่ ek | ◌้ tho | ◌๊ tri | ◌๋ chattawa |
|---|---|---|---|---|---|---|---|
| Mid class | mid | low | low | low | falling | high | rising |
| High class | rising | low | low | low | falling | — | — |
| Low class | mid | high | falling | falling | high | — | — |
Mai tri (◌๊) and mai chattawa (◌๋) only occur on mid-class consonants — hence the dashes.