Questions & Answers about Otkud to znaš?
In this sentence, otkud means something like how come, where did you get the idea, or literally from where.
It is often used when you are surprised that someone knows something. So it is not only about physical origin; it can also ask about the source of someone's knowledge.
Both can relate to from where, but otkud often sounds more conversational and more expressive, especially in questions like this one.
- Otkud to znaš? = How do you know that? / How come you know that?
- Odakle to znaš? also works and is very common, but it can sound a little more neutral or literal: From where do you know that?
In many everyday situations, they overlap, but otkud often carries more surprise.
Here to means that.
So Otkud to znaš? is literally something like How do you know that?
This to refers to some fact, information, or statement already mentioned or understood from context.