Mixed martial arts weight classes

Prior to state sanctioning, weight classes were not mandatory since the competitions were held without the approval of the athletic commissions.

In 2000, the Unified Rules of Mixed Martial Arts were codified by the New Jersey State Athletic Commission.

The Unified Rules designate limits for fourteen different weight classes in mixed martial arts; all definitions and measurements are in pounds.

Singapore-based ONE Championship banned weight-cutting by dehydration in December 2015 and holds fights based on a competitor's "walking weight", rather than pre-fight weigh-ins.

Some organizations that recognize women's championships also sanction a separate atomweight title with a 105 pounds (48 kg) limit.