Unfortunately there is no undisputed heavyweight champion.
The current heavy weight champion of boxing is Vladimir Klitschlow. He is from the Ukraine and weighs 243 pounds, or 220 kilograms.
Muhammad Ali
vladimir klitschko vladimir klitschko
From April 5, 1915 to July 4, 1919 - Heavy weight boxing champion - Jess Willard ( American )
Chris Archiballs. Great fighter from the mean streets.
Jack Johnson
Sonny Liston
rocky balboa
Wasn't Wladimir in as champion at that point(?)
Jack Johnson
wilfredo benitez
Ingemar Johnasson