There’s something timeless about a good knock-knock joke. They’re simple. They’re silly. And they never go out of style. Whether you’re 7 or 70, there’s a weird joy in going back and forth with a cheesy setup and a groan-worthy punchline.
We’ve rounded up 20 of the best classic knock-knock jokes — funny, clean, and perfect for all ages. Use them to crack up your kids, lighten the mood at the office, or just make someone smile.
Let’s knock this out.
The All-Time Favorites
- Knock, knock.
Who’s there?
Boo.
Boo who?
Don’t cry — it’s just a joke! - Knock, knock.
Who’s there?
Lettuce.
Lettuce who?
Lettuce in, it’s freezing out here! - Knock, knock.
Who’s there?
Cow says.
Cow says who?
No silly — cow says moo! - Knock, knock.
Who’s there?
Atch.
Atch who?
Bless you! - Knock, knock.
Who’s there?
Olive.
Olive who?
Olive you!
Punny & Playful Knock-Knocks
- Knock, knock.
Who’s there?
Harry.
Harry who?
Harry up and answer the door! - Knock, knock.
Who’s there?
Tank.
Tank who?
You’re welcome! - Knock, knock.
Who’s there?
Dishes.
Dishes who?
Dishes the police — open up! - Knock, knock.
Who’s there?
Butter.
Butter who?
Butter let me in or I’ll freeze! - Knock, knock.
Who’s there?
Nana.
Nana who?
Nana your business!
Jokes for the Little Ones
- Knock, knock.
Who’s there?
Boo hoo.
Boo hoo who?
Stop crying, it’s just a joke! - Knock, knock.
Who’s there?
Donut.
Donut who?
Donut forget to smile today! - Knock, knock.
Who’s there?
Ice cream.
Ice cream who?
Ice cream every time I see a scary movie! - Knock, knock.
Who’s there?
Owls say.
Owls say who?
Yes, they do! - Knock, knock.
Who’s there?
Cows go.
Cows go who?
No, silly — cows go moo!
For a Laugh Anywhere, Anytime
- Knock, knock.
Who’s there?
Woo.
Woo who?
Don’t get too excited — it’s just me. - Knock, knock.
Who’s there?
Stopwatch.
Stopwatch who?
Stopwatch you’re doing and open the door! - Knock, knock.
Who’s there?
Broken pencil.
Broken pencil who?
Never mind, it’s pointless. - Knock, knock.
Who’s there?
Ya.
Ya who?
No thanks, I use Google. - Knock, knock.
Who’s there?
Nobel.
Nobel who?
No bell, that’s why I’m knocking!
Wrap-Up
Knock-knock jokes are the comfort food of comedy. They’re simple, familiar, and always deliver a quick laugh — or at least a solid eye-roll. Keep this list handy for parties, family dinners, or any moment that needs a little lightness.
We’ll keep the jokes coming over at alldayjokes.com, so stay tuned for more classic fun, silly puns, and the world’s best worst jokes.