Boxing is a sport that has provided entertainment to the world for centuries.
Over the many years, it has produced countless legendary fighters who have gone down in history for their magnificent achievements.
But since the first world championship was won, only 21 fighters have retired undefeated with their belts around their waists.
Here’s every single professional boxing world champion who hung up their gloves without a single loss on their record.
A key figure in changing the landscape of women’s boxing. Michele Aboro retired as the undefeated WIBF super-bantamweight champion in 2001.
After becoming the first ever female Olympic boxing champion, Nicola Adams turned professional and won the WBO flyweight title. She was forced to retire in 2019 due to the risk of permanent vision loss.
The daughter of Muhammad Ali retired as the WBC, WIBA, IWBF and IBA female super middleweight champion and IWBF light heavyweight champion.
Laila also marked her name in history by fighting Joe Frazier’s daughter Jacqui in the first female main-event pay-per-view match.
Jimmy Barry held the world bantamweight championship from 1894 to 1899 and was undefeated in 70 professional bouts.
The Pride of Wales held world championships in two weight classes and remains the longest reigning super-middleweight world champion in boxing history.
Calzaghe held the WBO belt for more than 10 years and defended it on 20 occasions, a division record shared with Sven Ottke.
Kim Ji-won retired in 1986 as the undefeated super bantamweight champion. The South Korean fighter hung up his gloves in order to pursue a career in theatrical acting and singing.
Romanian fighter Mihai Leu was forced to step away from the ring in 1997 due to injury. He retired as the WBO welterweight champion and became a rally driver.
Ricardo López held the WBC mini flyweight title for eight years and defended it against a record 21 opponents. He also held the WBA and WBO titles until 1998 and retired as the IBF junior flyweight champion.
Rocky Marciano was the world heavyweight champion from 1952 to 1956 and is the only heavyweight title holder to retire undefeated.
Terry Marsh became the British, European and IBF light welterweight world champion during the 1980s.
Following his announcement that he had epilepsy, the Englishman became just the second European fighter to retire as an undefeated world champion.
Floyd Mayweather Jr
The biggest pay-per-view star of any sport enjoyed a gargantuan career and has since dipped in and out of retirement.
In 2008, Mayweather retired as the WBC welterweight champion but returned to the ring 21 months later. In 2015, Money defended his WBC, WBA and The Ring titles before retiring for the second time.
After becoming the first man to hold the world lightweight championship 1886 to 1893, Jack McAuliffe became the first European boxer in history to retire as an undefeated world champion.
Sven Ottke shares the record of defending his super-middleweight title against 20 opponents with Calzaghe. The German retired as undefeated world champion in 2004.
Now a politician, Dmitry Pirog once competed inside the ring and held the WBO middleweight title from 2010 to 2012.
He kept hold of his title until retirement, when a spinal injury forced him out of the sport.
Natascha Ragosina spent most of her professional career as the top female super middleweight boxer in the world.
She is the longest reigning WBA and WBC super middleweight champion and retired holding all super middleweight titles and two heavyweight belts.
As an all-round athlete, Kara Ro was awarded MVP in basketball, volleyball, co-ed volleyball, and track and field. She retired from boxing as the undefeated WIBA lightweight champion.
Harry Simon held a world title across two weights during his career and retired in 2002 as the WBO middleweight champion following a serious car crash.
The incident eventually saw him sentenced to prison for culpable homicide.
Pichit Sitbangprachan retired with a 24-0 record after winning the IBF flyweight title. He was viewed as an icon during the 1990s as Thailand did not have any boxing champions during that time.
(Trigger warning, suicide)
The Venezuelan boxer enjoyed an impressive career and held two titles in two different weight classes. Valero is the only WBC champion in history to win all his fights via knockout.
In 2010, after winning the WBC lightweight title, he took his own life in prison under suspicion of killing his wife.
The Son of God is ranked as BoxRec’s 12th greatest fighter of all time.
After winning an Olympic gold medal, he went on to win multiple world titles in two weight classes.He retired undefeated and as the WBA, WBO, IBF, and The Ring light heavyweight champion.
Wang Ya Nan
Wang Ya Nan retired in 2009 as the undefeated middleweight champion. She was the first Chinese boxer to hold the WBC women’s middleweight world title.