Boxing weight categories
Weight difference is the only criterion used to divide boxers into categories; an athlete's age determines only which specific set of weight limits and round length applies to them. Amateur boxing measures weight in kilograms; professional boxing has historically used pounds (1 kg ≈ 2.2 lb).
The weigh-in before a bout is a mandatory procedure confirming that a boxer genuinely meets the declared weight category.
Amateur boxing: categories by age group
The number and boundaries of weight categories in amateur boxing have changed several times over recent decades and differ for each age group. Below is a comparison of the weight limits (kg) for the main age groups, along with the closest professional category for reference:
| Category | Middle youths (boys) 13-14 | Older youths/girls 15-16 | Men/juniors 19-22 | Pro (kg) |
|---|---|---|---|---|
| Minimumweight | 46 | up to 46 | - | 47.6 (minimum) |
| Light flyweight | 48 | 48 | up to 48 | 49.0 |
| Flyweight | 50 | 50 | 51 | 50.8 |
| Super flyweight | - | - | - | 52.2 |
| Light bantamweight | 52 | 52 | - | - |
| Bantamweight | 54 | 54 | 54 | 53.5 |
| Super bantamweight | - | - | - | 55.2 |
| Featherweight | 57 | 57 | 57 | 57.2 |
| Super featherweight | - | - | - | 59.0 |
| Lightweight | 60 | 60 | 60 | 61.2 |
| Light welterweight | 63 | 63 | 63.5 | 63.5 |
| Welterweight | - | - | - | 66.7 |
| Super welterweight | 66 | 66 | 67 | - |
| Light middleweight | 70 | 70 | 71 | 69.9 |
| Middleweight | 75 | 75 | 75 | 72.6 |
| Super middleweight | - | - | - | 76.2 |
| Light heavyweight | 80 | 80 | 80 | 79.4 |
| Cruiserweight | - | - | 86 | 90.9 |
| Heavyweight | 90 | 80+ | 92 | - |
| Super heavyweight | - | - | 92+ | from 90.9 |
For women and junior women, a separate, more compact grid of categories is used (for example, 48, 50, 54, 57, 60, 63, 66, 70, 75, 81, and 81+ kg, depending on age group); at the Olympic Games, women's boxing historically used just 3 broad categories — flyweight (48-51 kg), lightweight (57-60 kg), and middleweight (69-75 kg) — although by the 2024 Games their number had grown to six (see the article "Boxing at the Olympic Games" for more).
Bouts in children's boxing (under 13, without rank classifications) are matched not by fixed categories but by an allowed weight difference: up to 1.5 kg for weights up to 40 kg, up to 2 kg for 40 to 64 kg, up to 3 kg for 64 to 70 kg, up to 4 kg for 70 to 78 kg, and up to 5 kg above 78 kg.
Professional boxing: 17 weight categories
Professional boxers compete in 17 weight categories, historically defined in pounds — hence the uneven kilogram values when converted:
| Category | Up to, kg | Up to, lb |
|---|---|---|
| Minimumweight | 47.63 | 105 |
| Light flyweight | 48.99 | 108 |
| Flyweight | 50.80 | 112 |
| Super flyweight | 52.16 | 115 |
| Bantamweight | 53.52 | 118 |
| Super bantamweight | 55.23 | 122 |
| Featherweight | 57.15 | 126 |
| Super featherweight | 58.97 | 130 |
| Lightweight | 61.24 | 135 |
| Light welterweight | 63.50 | 140 |
| Welterweight | 66.68 | 147 |
| Light middleweight | 69.85 | 154 |
| Middleweight | 72.57 | 160 |
| Super middleweight | 76.20 | 168 |
| Light heavyweight | 79.38 | 175 |
| Cruiserweight | 90.89 | 200 |
| Heavyweight | over 90.89 | over 200 |
A championship belt is contested in every professional weight category. Today the most prestigious belts belong to four sanctioning organizations — WBC, WBA, IBF, and WBO; a separate honorary (non-tournament) belt is also awarded by The Ring magazine. A boxer who holds all four tournament belts in a single category at the same time is considered the undisputed world champion. For more on these organizations, their history, and how they differ from one another, see the page "Boxing Around the World".