There are 17 weight classes in professional boxing, and five major recognised belts for each of the divisions: The WBA (World Boxing Association), WBC (World Boxing Council), IBF (International Boxing Federation), WBO (World Boxing Organization) and The Ring.
There are four recognised major bodies in boxing, the WBA, WBC, IBF and the WBO. The Ring title is awarded by American boxing magazine, The Ring, and has been done since 1922.
The mixture of belts and champions means that there is only a rare occasion when a class can be fully unified to produce an undisputed champion.
Boxers often fight across weight classes in order to maximise their chances of success, and Manny Pacquiao is currently the only fighter to have won titles in eight divisions.
Here is every champion in each of boxing's weight class.
Heavyweight
- WBA: Oleksandr Usyk
- WBC: Tyson Fury
- IBF: Oleksandr Usyk
- WBO: Oleksandr Usyk
- The Ring: Oleksandr Usyk
Bridgerweight
- WBC: Lukasz Rozanski
Cruiserweight
- WBA: Arsen Goulamirian
- WBC: Noel Gevor
- IBF: Jai Opetaia
- WBO: Chris Billam-Smith
- The Ring: Jai Opetaia
Light heavyweight
- WBA: Dmitry Bivol
- WBC: Artur Beterbiev
- IBF: Artur Beterbiev
- WBO: Artur Beterbiev
- The Ring: Vacant
Super middleweight
- WBA: Canelo Alvarez
- WBC: Canelo Alvarez
- IBF: Canelo Alvarez
- WBO: Canelo Alvarez
- The Ring: Canelo Alvarez
Middleweight
- WBA: Erislandry Lara
- WBC: Jermall Charlo
- IBF: Janibek Alimkhanuly
- WBO: Janibek Alimkhanuly
- The Ring: Vacant
Super welterweight/Junior middleweight
- WBA: Jermell Charlo
- WBC: Jermell Charlo
- IBF: Jermell Charlo
- WBO: Tim Tszyu
- The Ring: Jermell Charlo
Welterweight
- WBA: Terence Crawford
- WBC: Terence Crawford
- IBF: Jaron Ennis
- WBO: Terence Crawford
- The Ring: Terence Crawford
Super lightweight/Junior welterweight
- WBA: Rolando Romero
- WBC: Regis Prograis
- IBF: Subriel Matias
- WBO: Teofimo Lopez
- The Ring: Teofimo Lopez
Lightweight
- WBA: Devin Haney
- WBC: Shakur Stevenson
- IBF: Devin Haney
- WBO: Devin Haney
- The Ring: Devin Haney
Super featherweight/Junior lightweight
- WBA: Hector Luis Garcia
- WBC: O'Shaquie Foster
- IBF: Joe Cordina
- WBO: Emanuel Navarrete
- The Ring: Vacant
Featherweight
- WBA: Vacant
- WBC: Rey Vargas
- IBF: Luis Alberto Lopez
- WBO: Robeisy Ramirez
- The Ring: Vacant
Super bantamweight/Junior featherweight
- WBA: Marlon Tapales
- WBC: Naoya Inoue
- IBF: Marlon Tapales
- WBO: Naoya Inoue
- The Ring: Vacant
Bantamweight
- WBA: Takuma Inoue
- WBC: Alexandro Santiago
- IBF: Emmanuel Rodriguez
- WBO: Jason Maloney
- The Ring: Vacant
Super flyweight/Junior bantamweight
- WBA: Kazuto Ioka
- WBC: Juan Francisco Estrada
- IBF: Fernando Martinez
- WBO: Juno Nakatani
- The Ring: Juan Francisco Estrada
Flyweight
- WBA: Artem Dalakian
- WBC: Julio Cesar Martinez
- IBF: Sunny Edwards
- WBO: Jesse "Bam" Rodriguez
- The Ring: Vacant
Light/Junior flyweight
- WBA: Kenshiro Teraji
- WBC: Kenshiro Teraji
- IBF: Adrian Curiel
- WBO: Jonathan Gonzalez
- The Ring: Kenshiro Teraji
Minimumweight/Mini flyweight
- WBA: Thammanoon Niyomtrong
- WBC: Yudai Shigeoka
- IBF: Ginjiro Shigeoka
- WBO: Oscar Collazo
- The Ring: Vacant
You can read more on how the world championship system works in boxing here.