🇧🇷 Portuguese phrases

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

The SPAIKING TeamJuly 27, 2026
Eu não sei
"I don't know" in Portuguese · say it like ayoo now say

The most natural way to say "I don't know" in Portuguese is Eu não sei. 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

Não sei
A more casual way to say it
Eu não tenho certeza
Used when expressing 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 contexts. It's a straightforward way to express a lack of knowledge.

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 Portuguese

PortugueseEnglish
Desculpe, eu não sei a resposta.Sorry, I don't know the answer.
Common mistake
Learners often forget to include the subject 'eu', but it's common to say just 'não sei' in casual conversation.

The fastest way to remember it

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

Frequently asked questions

How can I express uncertainty in Portuguese?

You can say 'Eu não tenho certeza' to express that you are unsure.

Learn Portuguese by speaking it

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