In Bruges
Being John Malkovich
M.P. & the Holy Grail
I have the impression that Blazing Saddles and Airplane! are the safe answers if you want to seem with it. For some reason, these two movies are darlings of the internet and get referenced constantly.
I agree that Blazing Saddles was smirk inducing, but that’s about it.
Blazing Saddles
Young Frankenstein
History of the World, part 1
and for a bonus, Spaceballs
I would say “Most of the above” because I can’t narrow it down to three. One recent movie that hasn’t been mentioned and I think deserves an Honorable Mention is What We Do In The Shadows.
Airplane!
Young Frankenstein
Dr. Strangelove
Sent from my SM-N910V using Tapatalk
It looks like I’m going to have to watch A Fish Called Wanda.
And I’ll add Flash Gordon.
Airplane! really is that funny. I saw it in the theater with my grandparents when I was 7 and it was just as funny then as it is now. It makes fun of absolutely everyone and everything in rapid fire fashion for the entire length of the movie but it isn’t juvenile (although it can be). It uses just about every type of humor there is from toilet humor to slapstick to subtle cultural references and it never lets up even after the credits are done. That is some very talented writing backed up by very good acting.
Some studies show it has the highest laughs per minute of any movie ever made scoring an impressive 3 per minute. I own it and watch it fairly frequently. It really is that funny. The only movie that comes close for me is There’s Something About Mary.
**The Jerk
A Christmas Story
Dumb and Dumber
**
In college I fell in love at first ‘sight’ with a girl I had just met who responded to something I said by throwing out a quote from The Jerk. I responded in kind and we went back and forth like that for a while and then spent the rest of the evening and the next several months together.
Did you pick out a thermos for her?
Airplane
Caddy Shack
Man on the Moon
His Girl Friday
A Funny Thing Happened on the Way to the Forum – clever lyrics, still funny, in spite of the sexism.
A Fish Called Wanda
Airplane!
Trading Places
The Big Lebowski
Close behind:
Monty Python and the Holy Grail
Galaxy Quest
Liar Liar
Dave
Animal House
There’s Something About Mary
It’s a Mad, Mad, Mad, Mad World
True Lies
Blazing Saddles
High Anxiety
Notting Hill
Hot Fuzz
What’s Up, Doc?
Paper Moon
Finding Nemo
Heaven Can Wait
What’s Up, Tiger Lily?
9 to 5
Dead Men Don’t Wear Plaid
Ghostbusters
Midnight Run
Back to the Future
Hot Shots!
Sleeper
Dr. Strangelove
Raising Arizona
Monty Python and the Life of Brian
A lot of funny movies listed here, but I’ll “The Man With Two Brains.”
Kentucky Fried Movie
Brewster’s Millions
The Great Outdoors
They might not be my absolute top favorites, but I didn’t see them listed. And I will happily rewatch those anytime. 
Top Secret!
Real Genius
Young Frankenstein
O Brother Where Art Thou
The Odd Couple
Tootsie
Life of Brian
The Big Lebowski
The Producers
The extra best thermos that money can buy!
…three favorite movies that make you roar with laughter!
Some of these favorites I cant see as something to roar about.
I cant recall roaring laughter movies at this time
(Surely there are)
Of what has been mentioned so far:
I do like (iNPO)
1-Planes Trains and Auto’s :D-I can watch that several times a year
2-Airplane :D-Honorable mention only because I cant watch it that often
(Sometimes time can make you forget the funny parts and then you enjoy them again)
3-Raising Arizona 
Honorable mention: Liar Liar
Caveats:):
Melissa McCarthy movies are mostly good ((I really like MM) with the exception of Spy, its good but I dont care for Jason Statham’s character. And…St Vincent
Something like Bruce Almighty is funny too but I’d like comedies that dont have a serious or sad part. Overall BA was funny!
Comedies and SciFi are my favorite genres but romantic comedies…where’s a puke smilie? :dubious::dubious:
I’ve already cited my three, but I’m popping back in to express a little disappointment that there is no love for the early classics: WC Fields, Marx brothers, Chaplin. Even Bob Hope (whom I find largely unfunny but I do like the Road To… movies).
mmm