31 is a 2016 American horror film written, directed, and produced by Rob Zombie, and starring an ensemble cast featuring Sheri Moon Zombie, Jeff Daniel Phillips, Lawrence Hilton-Jacobs, Meg Foster, Richard Brake, Jane Carr, Judy Geeson, E.G. Daily, and Malcolm McDowell.

A period piece set in 1976, the film is about five carnies, who are kidnapped by a gang of homicidal clowns called "The Heads". The carnies are forced to play a survival game called "31", where they are chased by the clowns through a maze of rooms for over 12 hours. The penalty for capture is torture and murder, while bets are placed on the carnies' progress.

The film was crowdfunded online twice at fanbacked.com. At a test screening, Zombie compared 31 to his 2005 film The Devil's Rejects. It received mixed reviews, with multiple critics deeming it unoriginal.