With 17 weight classes in boxing and four major sanctioning bodies that bestow world titles, keeping track of who holds each of the belts can be difficult -- especially when there are sometimes multiple titlists in each organization because of interim and secondary belts.
To make it easier for boxing fans, below is a quick reference chart of who holds each of the titles in the four organizations
To check the top 10 fighters in each division, visit ESPN's divisional rankings.
For a list of the best fighters regardless of weight class, check ESPN's pound-for-pound rankings.
Heavyweight (Unlimited)
WBO: Oleksandr Usyk
IBF: Oleksandr Usyk
WBA: Oleksandr Usyk*
WBC: Tyson Fury
*Daniel Dubois is the WBA "regular" heavyweight champion
Cruiserweight (200 lbs.)
WBO: Lawrence Okolie
IBF: Mairis Briedis
WBA: Arsen Goulamirian*
WBC: Ilunga Makabu
*Ryad Merhy is the WBA "regular" cruiserweight champion
Light heavyweight (175 lbs.)
WBO: Joe Smith Jr.
IBF: Artur Beterbiev
WBA: Dmitry Bivol
WBC: Artur Beterbiev
Super middleweight (168 lbs.)
WBO: Canelo Alvarez
IBF: Canelo Alvarez
WBA: Canelo Alvarez*
WBC: Canelo Alvarez
*David Morrell is the WBA "regular" super middleweight champion
Middleweight (160 lbs.)
WBO: Demetrius Andrade
IBF: Gennadiy Golovkin
WBA: Gennadiy Golovkin*
WBC: Jermall Charlo**
*Erislandy Lara is the WBA "regular" middleweight champion
**Canelo Alvarez is the WBC "franchise champion"
Junior middleweight (154 lbs.)
WBO: Jermell Charlo
IBF: Jermell Charlo
WBA: Jermell Charlo
WBC: Jermell Charlo
Welterweight (147 lbs.)
WBO: Terence Crawford
IBF: Errol Spence Jr.
WBA: Errol Spence Jr.*
WBC: Errol Spence Jr.
*Eimantas Stanionis is the WBA "regular" champion
Junior welterweight (140 lbs.)
WBO: Josh Taylor
IBF: Josh Taylor
WBA: Vacant
WBC: Josh Taylor
Lightweight (135 lbs.)
WBO: Devin Haney
IBF: Devin Haney
WBA: Devin Haney*
WBC: Devin Haney**
*Gervonta Davis is the WBA "regular" lightweight champion
**Devin Haney is the WBC "franchise" lightweight champion
Junior lightweight (130 lbs.)
WBO: Shakur Stevenson
IBF: Joe Cordina
WBA: Roger Gutierrez
WBC: Shakur Stevenson
Featherweight (126 lbs.)
WBO: Emanuel Navarrete
IBF: Josh Warrington
WBA: Leo Santa Cruz*
WBC: Mark Magsayo
*Leigh Wood is the WBA "regular" featherweight champion
Junior featherweight (122 lbs.)
WBO: Stephen Fulton
IBF: Murodjon Akhmadaliev
WBA: Murodjon Akhmadaliev
WBC: Stephen Fulton
Bantamweight (118 lbs.)
WBO: Paul Butler
IBF: Naoya Inoue
WBA: Naoya Inoue
WBC: Naoya Inoue
Junior bantamweight (115 lbs.)
WBO: Kazuto Ioka
IBF: Fernando Martinez
WBA: Juan Francisco Estrada*
WBC: Jesse Rodriguez**
*Joshua Franco is the WBA "regular" junior bantamweight champion
**Juan Francisco Estrada is the WBC "frachise" junior bantamweight champion
Flyweight (112 lbs.)
WBO: Junto Nakatani
IBF: Sunny Edwards
WBA: Artem Dalakian
WBC: Julio Cesar Martinez*
*McWilliams Arroyo is the WBC interim flyweight champion
Junior flyweight (108 lbs.)
WBO: Jonathan Gonzalez
IBF: Felix Alvarado
WBA: Hiroto Kyoguchi*
WBC: Kenshiro Teraji
*Esteban Bermudez is the WBA "regular" junior flyweight champion
Strawweight (105 lbs.)
WBO: Masataka Taniguchi
IBF: Rene Mark Cuarto
WBA: Knockout CP Freshmart*
WBC: Petchmanee CP Freshmart
*Erick Rosa is the WBA "regular" strawweight champion