Highest boxing knockout percentage by a middleweight champion

The highest knockout percentage by a middleweight champion boxer is 91.67% and was achieved by Gennady Golovkin (Kazakhstan), who achieved 33 knockouts in 36 bouts between 6 May 2006 to 10 September 2016.

Golovkin has won his last 23 fights by way of knockout, most recently stopping the previously undefeated Kell Brook (UK) in a WBC, IBF, IBO title fight in London. The only three fighters to have gone the distance with Golovkin in professional bouts are Mehdi Bouadla, Ian Gardner and Amar Amari in the early stages of his career.