What Is Thai Transliteration?
Thai transliteration (also called romanization) is writing Thai words in the Roman alphabet so readers who don't know Thai script can pronounce them. Because Thai is a tonal language, good transliteration carries more than the letters: it must show each syllable's tone and vowel length, or the pronunciation is lost.
This tool does three things to any Thai text you paste: it segments the text into words (Thai is written without spaces), romanizes every word with tone diacritics, and shows per-word meanings plus a translation of the whole passage.
How the Tone Marks Work
Thai has five tones, and this tool marks every syllable's tone directly on the vowel — the part most phrasebook spellings throw away:
| Tone | Mark | Example |
|---|---|---|
| Mid | unmarked | maa |
| Low | à | mài |
| Falling | â | mây |
| High | á | máa |
| Rising | ǎ | mǎa |
Long vowels are doubled (aa, ii) and syllables are hyphen-separated, so the spelling always tells you both the melody and the length of every syllable. New to tones? Our five-tones guide lets you hear all five in one syllable.
Why Thai Words Have So Many English Spellings
The same Thai greeting appears in English as sawasdee, sawatdee, and sawadee— and none of them tell you the tones. That's because there are several competing systems: the government's RTGS standard (used on road signs — no tones, no vowel length), academic IPA, the Paiboon system used in some textbooks, and countless ad-hoc spellings. They aren't interchangeable, which is why learners see a different spelling in every phrasebook.
This tool uses one consistent, IPA-based system everywhere: the greeting above is sa-wàt-dii, with the low tone where it belongs. Every lesson and article on SornSabai uses the same system, so a word never changes its spelling on you.
Transliteration, Romanization, or Translation?
Transliteration and romanization mean nearly the same thing for Thai: converting Thai script into Roman letters that show the pronunciation. Translation converts the meaning into another language. This tool does both — the romanized line tells you how to say it, the English line tells you what it means, and tapping a word shows its dictionary senses.
Reading the script yourself is the long-term upgrade: Thai spelling encodes the exact tone of every word. When you're ready, start with our Thai alphabet guide or the first free lesson.
FAQ
What is Thai transliteration?
Thai transliteration is writing Thai words in the Roman alphabet so their pronunciation is readable without knowing Thai script. Good Thai transliteration also marks the tone and vowel length of each syllable, since both change a word's meaning.
What is the best way to transliterate Thai?
Use a system that marks all five tones and distinguishes short from long vowels — an IPA-based system does both. The official RTGS romanization seen on Thai road signs drops tones and vowel length, so it cannot tell you how a word actually sounds.
Why is the same Thai word spelled differently everywhere?
Several romanization systems coexist — RTGS, IPA-based systems, Paiboon, and informal spellings — and most casual sources mix them. The spellings sawasdee, sawatdee, and sawadee are all the same word. This site uses one consistent IPA-based system with tone marks.
Is this Thai transliteration tool free?
Yes — paste any Thai text and get segmentation, romanization with tone marks, per-word meanings, and a translation, free and without signing up.