A: How long should we bake this pie?

    B: Your guess is as good as mine.

    Note: What’s the origin of this idiom? Your guess is as good as mine. Well, I’m just kidding. It’s a pretty straightforward idea expressed clearly and succinctly that, repeated often enough, has become a sort of set phrase. It doesn’t contain analogies, similes, or metaphors, so it’s not difficult to understand. When we don’t know something, we usually take a guess. Therefore, this idiom means “If you ask me, well, I do not know the answer to that question.”