How to say thank you in Thai (and get khrap/kha right)

To say thank you in Thai, say khob khun (ขอบคุณ) and add khrap if you're a man or kha if you're a woman: khob khun khrap or khob khun kha. Pair it with a small wai — palms together, slight bow — for extra warmth, though the words alone are enough in most situations.

Khob khun vs. khob jai: two levels of thanks

Khob khun (ขอบคุณ) is the standard, polite "thank you" — safe with strangers, staff, elders, and anyone you're not close to. There's also a more casual version, khob jai (ขอบใจ), which Thai speakers use with friends, family, and people younger or lower in status than themselves — a boss thanking an employee, a parent thanking a child. As a visitor, khob khun is the one to default to; khob jai directed at someone clearly senior to you can land oddly, the way thanking your boss with "thanks, buddy" would in English.

If you're building out beyond just "thank you," the basic Thai phrases guide rounds up greetings, numbers, and food and transport words that come up just as often.

What khrap and kha actually mean

Khrap and kha don't translate into English words of their own — they're politeness particles, added to the end of a sentence to mark it as courteous. Which one you use depends entirely on your own gender, not the gender of the person you're speaking to: men say khrap, women say kha, in every context. Thai speakers attach them constantly — to greetings, requests, answers, and thank-yous — and a sentence without one isn't wrong, just blunter.

The kha/ka distinction most guides skip

Here's the part that trips up even careful learners: the female particle has two forms, not one, and they're not interchangeable. Ka (คะ), with no tone mark, has a sharp, high tone, and it's used for questions and for calling out to get someone's attention. Kha (ค่ะ), marked with a tone mark, has a falling tone, and it's used to end statements — including "thank you."

So khob khun kha (ขอบคุณค่ะ), with the falling tone, is correct for saying thank you. If a woman is instead asking a question or trying to get someone's attention — calling "excuse me!" to a waiter, for instance — the high-toned ka is what she'd reach for instead. The two spellings, ค่ะ and คะ, look almost identical on the page, which is exactly why the distinction gets lost in a lot of beginner material.

Khrap has no such split — it's ครับ (kráp) every time, statement or question, always the same tone. In fast, casual speech you'll often hear it clipped to something closer to "kap," dropping the r sound, which is normal and not a mistake on the speaker's part.

When to use it, and when Thais skip it

Khrap and kha are expected in service interactions, with strangers, and with anyone older than you — a shop clerk, a hotel receptionist, a tuk-tuk driver. Among close friends and within families, Thai speakers often drop the particle entirely, especially in fast back-and-forth conversation; adding it there can even read as unnecessarily formal, the way "thank you very much indeed" would among old friends in English. If you're a visitor and want a play-it-safe rule: keep the particle on with anyone you'd shake hands with rather than hug.

Thanking someone with a wai

A small wai alongside khob khun khrap/kha adds visible warmth — common when someone hands you something, gives you directions, or does you a specific favor. It isn't required for routine service interactions like paying a bill, where the words alone are the norm. The gesture itself, and when Thais expect it versus when a nod will do, is covered in more detail in how to say hello in Thai, since it's the same wai used for both greetings and thanks.

Hearing the difference between kha's falling tone and ka's high tone is far easier by ear than from a page of transliteration. Thai Phrasebook, an offline Thai phrasebook app with 700+ real-world phrases across 16 categories, plays khob khun and other everyday phrases as native audio at full and slow speed, with word-by-word breakdowns that flag exactly this kind of particle nuance.

FAQ

What's the difference between khob khun and khob jai?

Khob khun is the general, polite "thank you," safe in any situation. Khob jai is a casual, familiar "thanks," typically used toward people younger or lower in status than the speaker, or between close friends. When unsure, khob khun is the safer default.

Why do I sometimes hear kha and other times ka?

They're both the female particle, but with different tones and different jobs. Kha (falling tone) ends statements, including thank-yous. Ka (high tone) is used for questions and for calling out to someone. Men don't face this split — khrap covers both.

Is it rude to say khob khun without khrap or kha?

Not rude, just less polished — like leaving "please" off a request in English. It's understood fine, and close friends often skip the particle with each other, but adding it with staff, strangers, or elders is the more polite default.

Do you say thank you differently to a monk?

Thai speakers generally use more formal, respectful language around monks in general, but khob khun khrap paired with a wai raised a bit higher than usual is an appropriate and safe way for a visitor to express thanks to one.