How to Say “I don't understand” in Thai
ไม่เข้าใจ
mây khâw-cay
I don't understand
ค่ะ and ครับ are polite particles — they depend on the speaker's gender, not the listener's.
When to use it
ไม่ (mâi) is "not," เข้าใจ (khâo-cay) is "to understand" — literally "to enter the heart." Follow with พูดอีกทีได้ไหม (phûut-ìik-thii-dâai-mǎy) — "could you say that again?" — or พูดช้าๆ หน่อย — "please speak more slowly."
Why you've seen it spelled differently
You may have seen ไม่เข้าใจ written as: mai khao jai, mai khaojai, mai kow jai.
There is no single standard for writing Thai in the Roman alphabet — phrasebooks, road signs, and tourist guides each follow a different system, and many just invent their own spellings. The romanization on this page uses a consistent IPA-based system that marks all five tones and distinguishes short from long vowels. The same word always gets the same spelling. Paste any Thai to see it romanized →
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