In this post, you will learn some common ways of saying I don't know in Brazilian Portuguese.
This is the most common way of saying I don't know in Brazilian Portuguese - using the verb saber conjugated with eu.
To sound more natural you can leave eu out and just say Não sei!
This is the equivalent of I have no idea.
Instead of the verb ter (to have) you can use the verb fazer (to make, to do).
You can insert the word nem as emphasis. This literally means 'not even'.
You can also insert nem after the verb fazer.
Brazilians often use the short version of the two phrases above: Nem ideia! - which could be translated No idea'
You insert a mínima after the verb. It literally means the minimum, but it would be like saying I don't have the faintest/slightest idea.
You can also insert a mínima after the verb fazer.
Literally Sei lá means I know there - but it's used as an expression to mean something like dunno - i.e. it conveys the idea that you not only don't know the answer but that you don't really care, so it's a bit dismissive.