Check out my rankings within each division by clicking on the links below. If there is a lineal champion in a weight class, he is ranked No. 1.
Who is the best fighter regardless of weight class? See ESPN's pound-for-pound rankings.
For a list of the current champions in all weight classes, click here.
Note: Results through April 25. In an effort to provide the most up-to-date rankings, ESPN.com's division-by-division boxing rankings will be updated every Tuesday.
More divisional rankings
Middleweight - Junior middleweight - Welterweight - Junior welterweight
Lightweight - Junior lightweight - Featherweight - Junior featherweight
Bantamweight - Junior bantamweight - Flyweight - Junior flyweight/Strawweight
HEAVYWEIGHT DIVISION (UNLIMITED)
1. Tyson Fury (25-0)
England's Fury ended the 9½-year reign of Wladimir Klitschko in November 2015 but twice pulled out of their contractually mandated rematch in 2016 because of a litany of personal problems that have kept him away from the ring. Fury twice tested positive for cocaine and has admitted to alcohol and mental health issues. On top of that, Fury faces allegations that he used performance-enhancing drugs in a fight before he faced Klitschko, which could lead to a multiyear ban from the sport. With so many issues, and unable to defend the belts, Fury gave up his alphabet titles but remains lineal champion. He claimed he would be back on May 13, but there's no way that will happen considering he needs to get a license from British regulators and is not even close to being in fighting shape. Now he says he's hoping to return in July.
2. Wladimir Klitschko (64-4)
During his 9½-year title reign -- second longest in heavyweight history -- Klitschko successfully defended the title 18 times, third most in division history. He had an 11½-year undefeated run and won 22 fights in a row. Then he defended against England's Tyson Fury in November 2015 and showed virtually nothing, perhaps growing old before our eyes. But a loss is a loss, and Klitschko's historic reign came to an ignominious end. The rematch with Fury was twice called off because of Fury's personal issues, so Klitschko went without a fight in 2016. He will return in 2017 for a showdown with titleholder Anthony Joshua (18-0) at Wembley Stadium in London. Heavyweight title fights get no bigger. That's why Showtime and HBO are both televising it in the United States.
Next: April 29 vs. Joshua
3. Deontay Wilder (38-0)
Wilder, a tremendous puncher, has scored knockouts in all five of his title defenses, including on Feb. 25 when he stopped Gerald Washington in the fifth round. It was Wilder's first fight since knocking out Chris Arreola in July; Wilder broke his right hand and tore his right biceps in that bout and required surgery to repair both injuries. He hopes to meet Joseph Parker (22-0) in a title unification fight next, but he might instead have to fight a pointless mandatory defense against undeserving Bermane Stiverne (25-2-1), the man he easily outpointed for the belt in January 2015.
4. Luis Ortiz (27-0)
A 6-foot-4, 240-pound southpaw with raw power, Ortiz, a Cuban defector with tons of amateur experience, signed with adviser Al Haymon in March and was quickly added to the Shawn Porter-Andre Berto undercard to face journeyman Derric Rossy (31-12). However, Ortiz suffered a thumb injury and his fight was scrapped, though he remains a mandatory challenger for the Anthony Joshua-Wladimir Klitschko winner.
5. Anthony Joshua (18-0)
Joshua won the Olympic super heavyweight gold medal for Great Britain in 2012 and has steamrolled his first 18 opponents as a pro, including a two-knockdown, second-round knockout victory against paper titleholder Charles Martin in April to win a belt, and a seventh-round knockout of Dominic Breazeale in a one-sided thrashing in Joshua's first defense in June. Nothing was different in defense No. 2 on Dec. 10 when Joshua smashed journeyman Eric Molina in the third round, a victory that set up a megafight with former long-reigning champion Wladimir Klitschko (64-4).
Next: April 29 vs. Klitschko
6. Joseph Parker (22-0)
When Tyson Fury vacated his two sanctioning-body belts, it put New Zealand's Parker in position to face Andy Ruiz Jr. for one of the belts on Dec. 10. In one of the biggest sporting events in New Zealand history, Parker overcame a slow start and managed to edge Ruiz by majority decision to claim the title and become his country's first heavyweight titleholder. Parker's first defense was scheduled to be a mandatory against Hughie Fury (20-0), Tyson's first cousin, in New Zealand. But Fury pulled out with a supposed back injury two weeks before the bout, leaving Parker's team to find a new opponent.
Next: May 6 vs. TBA
7. Kubrat Pulev (24-1)
Bulgaria's Pulev, who got knocked out in a title shot against then-world champion Wladimir Klitschko in November 2014, has won four in a row since. On Dec. 3, Pulev's first fight in his home country, he hammered washed-up, out-of-shape former titlist Samuel Peter for three rounds. Peter quit with an apparent arm injury just after the bell rang to begin the fourth round. Pulev will be back to fight again in Bulgaria when he meets journeyman Kevin Johnson (30-7-1) in what should be an easy win.
Next: April 28 vs. Johnson
8. Andy Ruiz Jr. (29-1)
Ruiz, who has tremendous hand speed but is not always in the best condition, traveled to New Zealand to face Joseph Parker for a vacant title on Dec. 10 in a bid to become the first heavyweight of Mexican descent to win a world title. He came up just short of the goal, dropping a majority decision in a fight that was exceptionally close.
9. Dillian Whyte (20-1)
Whyte, the former British champion, outpointed former world title challenger Dereck Chisora on Dec. 10 in an epic slugfest that was one of the best fights of 2016. The victory was Whyte's fourth in a row since a knockout loss to Anthony Joshua in December 2015, and he deserves another meaningful fight. He'll be back to face Poland's Mariusz Wach (33-2), a former world title challenger, in an interesting fight.
Next: June 3 vs. Wach
10. Dominic Breazeale (18-1)
A 2012 U.S. Olympian, Breazeale gave a good account of himself in a seventh-round knockout loss challenging Anthony Joshua for his world title in June 2016 and bounced back to stop previously undefeated Izuagbe Ugonoh in the fifth round of a hellacious see-saw battle on Feb. 25 in a candidate for fight of the year.