The funniest cartoon series would be The Simpsons, season 3-8. However, since there are also 20-something seasons that are mediocre to not funny, I'd say that the most consistently funny cartoon would be Animaniacs. I can't recall any moments in its 5 season, 99 episode run where the quality noticeably dropped off. Furutama would be a close second, with 5 fantastic seasons and 2 great seasons.
For sentimental reasons, I'd say the funniest cartoon to me is either Regular Show or Mission Hill.

Honorable Mentions:
The Boondocks, season 1-3
Clone High
Daria
Gravity Falls
Spongebob, seasons 1-3
The Critic
Family Guy, pre-cancellation (I believe that's season 1-3? maybe 1-2)
American Dad
Rick and Morty
Ren and Stimpy
The Ripping Friends

It's not a cartoon, but if it counts I'd say Moral Orel is the greatest written "cartoon" if all time, both for comedy and tragedy. It's just also stop motion, so.

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Futurama was pretty great up to and including the movies. After that, it got incredibly awful.

I liked Simpsons seasons 1-2, though yeah 3-4 was the best, and by 10 it was dead.

at the risk of straying off track (but i already gave my answer so its ok), season 1 and 2 are definitely my favourites from a strictly story-telling perspective. My favourite jokes are obviously from 3-8, but some of my favourite moments were in those first 2 seasons.

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This.

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Linktree

-Earlier seasons of The Simpsons
-Wander over Yonder
-South Park
-Robot Chicken
-Beavis and Butthead
-King of the Hill, particularly the ones where Hank reacts to being surrounded by idiots. Or is that just about all of them?


Of the few episodes I've seen, it was a great first impression.

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Legacy custom music
A site where you can watch my YT videos AND be able to hit that dislike where your dislike will be visible to other people and not have to rely on a browser extension

nobody has even mentioned Ed Edd n Eddy what kind of fuckery is this

Honorable mentions:


- Ed Edd n Eddy the entire way through, thankfully Cartoon Network let it properly end with a movie, even
- How the fuck has nobody mentioned Popeye
- Spongebob seasons 1-3
- Fairly OddParents until around 1-2 seasons after Poof was introduced
- Looney Tunes until you get around the point where it's obvious when they're going to use the TNT joke for the 500th time
- Tom and Jerry until the shitty reboots where it was more voice acting than actual comedy
- Regular Show (especially the earlier seasons)
- The Powerpuff Girls until the new writers and reboots made it shit and painfully cringeworthy
- Chowder which had extremely bizarre yet clever humor