The sport of boxing is infamous for being saturated with belts. Each of the 17 weight divisions from heavyweight (200lbs+) all the way down to minimumweight (105lbs) has four major world titles and BBN have listed all of them here.
The WBA, WBC, IBF and WBO are boxing’s four recognised governing bodies, with IBO seen as a 'fringe' belt, but the associations can sometimes create superfluous extra belts. The WBA are notorious for this, much to fight fans' frustrations, with 'Regular' and 'Super' titles. It creates crazy conditions where a 'Super' champion will want to fight the lesser 'Regular' champion, such as Keith Thurman looking down on a fight with Manny Pacquiao right now.
In the list below, there are no ‘interim’, ‘diamond’, ‘silver’ or ‘gold’ titles, and certainly no ‘regular’ titles to keep things simple.
AJ also has the unrecognised IBO belt
Oleksandr Usyk has unified the entire cruiserweight division
Alberto Machado should in be the WBA champion, however they inexplicably classified him as ‘regular’ champion instead