I know! Right?!

It's pretty clear what the speaker is trying to convey: "I agree."

I agree with most of the other definitions, which provide details on the subtle context/audience-dependent connotations. I agree that phrase is annoying, used by speakers who use other annoying phrases like "my bad."

I would like to add to what has been said by providing side-by-side analogs; that is, alternative, equivalent but more acceptable expressions.
Example Expressions

I can't handle this idiot any more!
I know! Right?! OR Damn straight!

In wish I brought my swimsuit.
I know! Right?! OR You're telling me!

I like this 'double it for a buck' happy hour!
I know! Right?! OR You can say that again!

I was gunning for Miss Tipsy, but I just got shut down by her fat roommate!
I know! Right?! OR Join the club!

This is good sauce.
I know! Right?! OR Yes, it is.

Let's not go to the Bubble Club. It's so damn expensive!
I know! Right?! OR You got THAT right!

I have an idea: let's strip and go wallow in the mud puddles.
I know! Right?! OR You're preaching to the choir!

Our corporate holiday event was so cheap it was insulting.
I know! Right?! OR I couldn't agree more.

They are good at talking all sexy.
I know! Right?! OR Mmm hmm!!

This is the correct line for us.
I know! Right?! OR Right you are.

Tacos.
I know! Right?! OR Yeee-ah boooooooyeeee!!

We're in trouble NOW.
I know! Right?! OR No shit.

Tonight, we wear The Boots!
I know! Right?! OR Fuckin A right!
by TimmyT-SF November 28, 2023
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I Know its Over

I Know its Over by The Smiths is the greatest song of all time
by halfaperson December 06, 2024
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I don't know what to look up

What did you think was gonna pop up? THINK ABOUT HOW TO MAKE PROGRESS IN LIFE! THINK ABOUT WHAT YOU WILL DO! Learn some Spanish or meditate. Go for a jog come on, you got this!
Bob, (Searches "I don't know what to look up, then sees this) "I WILL FIX MY LIFE STEP BY STEP!
by tdude_yahyeet12 November 26, 2022
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I know you fucking lying

(Ikyfl) Its a saying that kinda means that what you just said is so crazy that it might as well be a lie
Him-Lol that was the girl that broke up with me
Friend- I know you fucking lying
by ifyou November 21, 2021
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Your already know
Guy 1: *deep voice impression*

Guy 3: I didn't know it could go that deep...

Guy 2: That’s what she said.
by Adudeidkcyan March 23, 2024
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