Mixed Martial Arts Weight Classes
Organizations will often adopt their own rules for weight limits, causing ambiguity in the sport regarding how a weight class should be defined. For a variety of reasons (largely historical), weight classes of the same name can be of vastly different weights.
Weight Classes in the United States
In 2000, the Unified Rules of Mixed Martial Arts were codified by the New Jersey State Athletic Commission – working with the California State Athletic Commission, who had worked extensively on regulation, but its sanctioning of MMA was not implemented due to state governmental issues surrounding the budgeting process. California officially sanctioned MMA on December 28, 2005, using the ruleset it helped devise five years previously.
Since then, to create uniformity in the United States, many state athletic commissions have assimilated these rules for mixed martial arts into their existing unarmed combat competition rules and statutes. For a promotion to hold mixed martial arts events in a state-sanctioned venue, the promotion must abide by the state athletic commission’s body of rules for weight limits.
Weight Classes under the Unified Rules
The Nevada State Athletic Commission has designated limits for nine different weight classes in mixed martial arts. Fighters must be weighed in lbs:
| Flyweight | - 125 lbs | - 57 kg |
| Bantamweight | - 135 lbs | - 61 kg |
| Featherweight | - 145 lbs | - 66 kg |
| Lightweight | - 155 lbs | - 70 kg |
| Welterweight | - 170 lbs | - 77 kg |
| Middleweight | - 185 lbs | - 84 kg |
| Light Heavyweight | - 205 lbs | - 93 kg |
| Heavyweight | - 265 lbs | - 120 kg |
| Super Heavyweight | No upper Weight Limit | |
Prior to state sanctioning, weight classes were not mandatory since the competitions were held without the approval of the athletic commissions. For instance, the Ultimate Fighting Championship introduced two weight classes at UFC 12: Heavyweight, which grouped competitors above 200 lb (91 kg), and Lightweight, which grouped competitors under 200 lb.
Weight divisions would undergo many changes in the coming years, but the ability of promotions to autonomously decide their own weight classes would eventually disappear after athletic commissions began supervising mixed martial arts.
Non-codified States and Exceptions
In the following states, MMA is legal but is not regulated by a local commission: Alabama, Alaska, Hawaii, Massachusetts, Minnesota, Montana, South Dakota, and Wyoming.
The most notable of these states is Hawaii, whose lack of codified restrictions on mixed martial arts allows promotions to set their weight limits as they see fit. Hawaii’s Rumble on the Rock has a welterweight champion at the unique weight of 175 lb (79.5 kg).
Promotions that hold events on Indian reservations are exempt from any restrictions, as they are outside the jurisdiction of state commissions.
Weight Classes in Japan
With no state or government laws regarding weight class restrictions, Japanese organizations are free to schedule bouts with little regard for weight differential. However, due to the increasingly competitive nature of the sport, weight is often seen as an unfair advantage over a smaller competitor; therefore, weight limits have been set by the promotions themselves. These limits differ from organization to organization. Japan uses the metric system.
Dream
Dream’s weight categories go by similar guidelines as the Unified Rules, differing only by a few pounds.
| Featherweight | - 145 lbs | - 67 kg |
| Lightweight | - 154 lbs | - 70 kg |
| Welterweight | - 168 lbs | - 76 kg |
| Middleweight | - 185 lbs | - 84 kg |
| Light Heavyweight | - 205 lbs | - 93 kg |
| Heavyweight | No upper Weight Limit | |
Pride
Pride Fighting Championship arranged one weight category for every ten kilograms, starting at 73 kg (161 lb) and ending at 93 kg (205 lb).
| Lightweight | - 161 lbs | - 73 kg |
| Welterweight | - 183 lbs | - 83 kg |
| Middleweight | - 193 lbs | - 93 kg |
| Heavyweight | No upper Weight Limit | |
Shooto
Shooto Japan has fixed weight divisions for lighter competitors.
| Bantamweight | - 123 lbs | - 56 kg |
| Featherweight | - 132 lbs | - 60 kg |
| Lightweight | - 143 lbs | - 65 kg |
| Welterweight | - 154 lbs | - 70 kg |
| Middleweight | - 167 lbs | - 76 kg |
| Light Heavyweight | - 187 lbs | - 85 kg |
K-1 Hero’s
K-1 Hero’s established weight classes around the time of their first mixed martial arts tournament.
| Middleweight | - 154 lbs | - 70 kg |
| Light Heavyweight | - 187 lbs | - 85 kg |
Weight classes in the United Kingdom
There is currently no Board of Control governing MMA in the UK and promotions can set weight classes as they see fit.
Cage Rage
Cage Rage weighs fighters using the metric system. Weight classes are in line with the Unified Rules of MMA.
| Featherweight | - 145 lbs | - 66 kg |
| Lightweight | - 155 lbs | - 70 kg |
| Welterweight | - 170 lbs | - 77 kg |
| Middleweight | - 185 lbs | - 84 kg |
| Light Heavyweight | - 205 lbs | - 93 kg |
| Heavyweight | No upper Weight Limit | |
