“I know, right?” I don’t know, why are you asking me?

I’ve always interpreted it as “I know what you mean, and we are in agreement, right?”

I say it often, and Ive never associated the “right?” with “do I know this?”

Just to make sure I’m understanding you correctly, you’re talking about an exchange like this?

Person 1: It sure is hot today.
Person 2: I know, right?

Thinking about some other conversational ways to respond, I think saying, “It sure is, isn’t it?” or, “Don’t I know it!” feel pretty similar. I wonder what it is that makes us ask rhetorical questions like that.

“What’s up?” It’s the direction in space opposite to the local gravitational field, why are you asking me?