Boxing is a complicated and convoluted sport with several world champions in each division.
Most observers recognise that we are now in a four-belt era, with the WBA, WBC, IBF and WBO all given credibility as legitimate world titles.
See the full list of the current men's boxing world champions below...
Heavyweight (200lbs+)
WBA - Oleksandr Usyk
WBC - Oleksandr Usyk
IBF - Oleksandr Usyk
WBO - Oleksandr Usyk
*Mahmoud Charr has the lesser WBA 'regular' belt
*Joseph Parker has the lesser WBO 'interim' belt
Bridgerweight (224lbs)
WBA - Muslim Gadzhimagomedov
WBC - Lawrence Okolie
*Kevin Lerena has the lesser WBC 'interim' belt
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Cruiserweight (200lbs)
WBA - Gilberto Ramirez
WBC - Noel Mikaelian
IBF - Jai Opetaia
WBO - Chris Billam-Smith
Light-Heavyweight (175lbs)
WBA - Dmitry Bivol
WBC - Artur Beterbiev
IBF - Artur Beterbiev
WBO - Artur Beterbiev
*David Benavidez has the lesser WBC 'interim' belt
Super-Middleweight (168lbs)
WBA - Canelo Alvarez
WBC - Canelo Alvarez
IBF - Canelo Alvarez
WBO - Canelo Alvarez
*David Morrell has the lesser WBA 'regular' belt
*David Benavidez has the lesser WBC 'interim' belt
Middleweight (160lbs)
WBA - Erislandy Lara
WBC - Carlos Adames
IBF - Janibek Alimkhanuly
WBO - Janibek Alimkhanuly
Super-Welterweight (154lbs)
WBA - Israil Madrimov
WBC - Sebastian Fundora
IBF - Bakhram Murtazaliev
WBO - Sebastian Fundora
*Serhii Bohachuk has the lesser WBC 'interim' belt
Welterweight (147lbs)
WBA - Terence Crawford
WBC - Mario Barrios
IBF - Jaron Ennis
WBO - Terence Crawford
*Eimantas Stanionis has the lesser WBA 'regular' belt
*Brian Norman has the lesser WBO 'interim' belt
Super-Lightweight (140lbs)
WBA - Isaac Cruz
WBC - Alberto Puello
IBF - Liam Paro
WBO - Teofimo Lopez
*Ismael Barroso has the lesser WBA 'interim' belt
Lightweight (135lbs)
WBA - Gervonta Davis
WBC - Shakur Stevenson
IBF - Vasyl Lomachenko
WBO - Denys Berinchyk
Super-Featherweight (130lbs)
WBA - Lamont Roach Jr
WBC - Robson Conceicao
IBF - Anthony Cacace
WBO - Emanuel Navarrete
*Albert Batyrgaziev has the lesser WBA 'interim' belt
*Oscar Valdez has the lesser WBO 'interim' belt
Featherweight (126lbs)
WBA - Nick Ball
WBC - Rey Vargas
IBF - Luis Alberto Lopez
WBO - Rafael Espinoza
*Brandon Figueroa has the lesser WBC 'interim' belt
Super-Bantamweight (122lbs)
WBA - Naoya Inoue
WBC - Naoya Inoue
IBF - Naoya Inoue
WBO - Naoya Inoue
Bantamweight (118lbs)
WBA - Takuma Inoue
WBC - Junto Nakatani
IBF - Ryosuke Nishida
WBO - Yoshiki Takei
Super-Flyweight (115lbs)
WBA - Kazuto Ioka
WBC - Jesse 'Bam' Rodriguez
IBF - Fernando Martinez
WBO - Kosei Tanaka
*David Jimenez has the lesser WBA 'interim' belt
*Pedro Guevara has the lesser WBC 'interim' belt
Flyweight (112lbs)
WBA - Seigo Yuri Akui
WBC - Vacant
IBF - Vacant
WBO - Vacant
Light-Flyweight (108lbs)
WBA - Kenshiro Teraji
WBC - Kenshiro Teraji
IBF - Sivenathi Nontshinga
WBO - Vacant
Minimumweight (105lbs)
WBA - Knockout CP Freshmart (Thammanoon Niyomtrong)
WBC - Melvin Jerusalem
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IBF - Ginjiro Shigeoka
WBO - Oscar Collazo