that's what I'm saying 

"I agree with you wholeheartedly"
"I couldn't have said it better myself"
could be an opinion about something good or bad

Those two just argue all night. They should just break-up.
That's what I'm sayin'

That was the best concert I've ever seen in my entire life!
That's what I'm sayin'!

that's what I'm saying by Webster Papadopolous July 13, 2004

That's what I'm sayin' 

When someone says something you agree with, don't just say "yeah" or "i agree" go all out and say "THAT'S WHAT I'M SAYIN' BRO!"

Phil:"Yo dude, Packers are probably going to win the 2010-2010 Super Bowl."
Don:"THAT'S WHAT I'M SAYIN'!"

That's what I'm sayin' by Call_Me_T R U T H January 19, 2011

i know! that's what im saying! 

a perfect way to end an argument when you realize you're wrong halfway through it.

1: Daniels Hall is really nice.
2: bullshit.
1: No, its awesome
2: fuck, it is the worst place ever.
3: yeah dude, that place reeks and is never clean. it sucks.
1: I know! that's what im saying!

i know! that's what im saying! by ma jones May 18, 2004

Thats what i'm sayin' 

I agree, trying to get a point accross, is unsure but tries to confide in you by using this phrase.

Agreeing when not even on subject, see example.

Usually heard before or after an elongated "breathing through the teeth" sounnd *See thhhhssshhssst, not unlike when a tradesman is about to tell you how much a repair is going to cost you.

Person 1 (saying phrase): Were you watching the game last night?
Person 2: Yeah that save was amazing the keeper made?
Person 1: Thats what i'm sayin'thhhhssshhssst.

Person 2: No you never you just asked if i seen the game?

Thats what i'm sayin' by urban spotter July 9, 2009