Dumber than a rock 

A guy named Michael who acts like he knows everything and does stupid shit.

Michael: How do you spell "sexist"
Me: You're dumber than a rock

Dumber than a rock by 093707053 July 3, 2018

Dumber than a rock on a bad day 

Dumber than a rock on a bad day, which would be dumber on the dumb scale compared to "Dumber than a rock".

Friend 1: Your dumber than a rock!
Friend 2: Your dumber than a rock on a bad day!
Friend 1: Shit.

Dumber than a rock on a bad day by jeffboi42 August 20, 2020

dumber than a box of rocks 

when ur pretty dumb. my mom says this to me all the time.

Ur dumber than a box of rocks
-what?
shut up dumbass

dumber than a box of rocks by barbarino April 18, 2005

dumber than a box of rocks 

Phrase describing a person who lacks the collective intelligence of a box of rocks; possibly a bit more intelligent or a bit less intelligent than a person who is dumb as a rock.

John lit a match so he could see where the gas was leaking out; he's dumber than a box of rocks.

dumber than a box of rocks by Rocky Balbowa December 20, 2007

dumber than a sack of rocks 

A Southern idiom for someone who is beyond stupid.

Dave: I tell you Bobby is dumber that a sack of rocks.
Laura: Why?
Dave: I asked him to meet me outside the movie theater, and asked inside or outside.
Example2:
Clerk: Your total is $10.05 Do you have a nickel?
Bobby: No, only 5 pennies.
Clerk: You are dumber than a sack of rocks.

dumber than a sack of rocks by fml November 19, 2007

Dumber than a Box of Rocks 

That guy name Jake from Rocket League

Jake is dumber than a box of rocks on any game we play

Dumber than a Box of Rocks by Thatboiinblue February 23, 2021

dumber than a bag of rocks 

where an individual that is really off and not quite there yet with the rest of his population.

you are "dumber than a bag of rocks"

dumber than a bag of rocks by youpapa420 February 28, 2022