Reviews provided by RottenTomatoes
New York Times:
A movie that fully lives up to its name, right down to an opening credit sequence rife with intentional misspellings and grammatical errors.
This is a long way from the social comedy of Jerry Lewis. The characters here are ultimately turned into punching bags or punch-line dispensers.
Dumb and Dumber, which features Carrey and Jeff Daniels as nitwits traveling cross-country, is a frayed string of gags posing as a movie. Carrey, though, does literal-minded doofdom with peerless enthusiasm.
The plot, of course, is merely an excuse for an endless series of gags, and the percentage of them that score is fairly high.
While I won't claim to have gone through this entire film without laughing, there are some long periods between chuckles.
Carrey, I am now convinced, is a true original. In The Mask, he had the screenplay and production to back him up. Here, the filmmaking is more uncertain.
San Francisco Chronicle:
Inspired, irreverent, spark-driven comedy that takes you places you never thought a movie would go -- even a Jim Carrey movie.
Given American cinema's current obsession with innocence and ignorance, at least this never romanticises its protagonists. They are genuinely, irredeemably, 100 per cent no-hopers.
The wholeheartedness of this descent into crude and rude humor is so good-natured and precise that it's hard not to partake in the guilty pleasures of the exercise.
An uneven collection of bodily function jokes, facial gyrations, sexual jibes and pedestrian slapstick.
An execrable catalogue of doody jokes, Dumb and Dumber is an abominable, abdominal comedy.