🇻🇳 Vietnamese phrases

How to Say "I don't know" in Vietnamese

The SPAIKING TeamJuly 27, 2026
Tôi không biết
"I don't know" in Vietnamese · say it like toy kohng beet

The most natural way to say "I don't know" in Vietnamese is Tôi không biết. Tap the speaker above to hear it, then say it back out loud. That is the fastest way to make it stick.

Other ways to say it

Mình không biết
More casual, often used among friends
Tôi không rõ
Slightly more formal, implies uncertainty

When to use it

Use this phrase when you genuinely do not have the information someone is asking for. It can be used in both formal and informal settings. It's a polite way to express your lack of knowledge on a topic.

Say it out loud, get corrected

Reading it is not the same as saying it. Practice "I don't know" and thousands more with an AI coach that listens.

Examples in Vietnamese

VietnameseEnglish
Tôi không biết câu trả lời cho câu hỏi này.I don't know the answer to this question.
Common mistake
Some learners might confuse it with 'Tôi không hiểu', which means 'I don't understand'.

The fastest way to remember it

Vocabulary you only read fades fast. Vocabulary you say out loud sticks. Hear Tôi không biết, repeat it a few times, then use it in a real sentence. SPAIKING lets you practice exactly that, speaking Vietnamese with a coach that corrects your pronunciation in real time. You can start with two free conversations.

Frequently asked questions

How do I say 'I don't know' in a more casual way?

You can say 'Mình không biết' when speaking with friends.

Learn Vietnamese by speaking it

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