While it is impossible to know for sure who has the heaviest hands in UFC history, Francis Ngannou is a safe bet. The heavyweight contender has the most potent recorded punch in the UFC institute with an incredible 129,161 units.
Even though it is undeniable that the Cameroonian fighter has exceptional strength and holds the highest recorded number in the PowerKube machine, the method used to calculate Ngannou's power is controversial.
The machine produced by the company StrikeCoach is not as popular worldwide, and it was only tested with some fighters. It is possible to affirm that Ngannou has the most potent punch among those who hit the PowerKube.
Ngannou's punch thrown at the PowerKube machine was estimated to have the same power as a small family car. UFC president Dana White said at the time of the test:
"Francis Ngannou has the world record for the most powerful punch. His punch is the equivalent to 96 horsepower, which is equal to getting hit by a Ford Escort going as fast as it can, and it's more powerful than a 12-pound sledgehammer swung from overhead."
However, since the PowerKube can't be trusted as a primary source for this since it is not widely used, what other components could be analyzed to find the heaviest hitter in the UFC?
Most knockout wins in UFC history
Derrick Lewis tied Vitor Belfort's record of most knockouts in the UFC with his win over Curtis Blaydes at UFC Fight Night 188. Lewis swang an uppercut that instantly sent Blaydes unconscious to the canvas.
That was Lewis' 12th victory via knockout, but unlike Belfort, his 12 KO victories were produced solely by his fists. Francis Ngannou is fast approaching, with eight out of his nine wins happening after a punch.
Other UFC knockout artists who have almost as many victories in that way as Lewis, such as Anderson Silva (11) and Michael Bisping (10), are more regarded for their technique instead of sheer punching power.
Other UFC fighters who can easily enter the conversation are Thiago Santos, who has eight knockout victories stemming from punches, Matt Brown (eight), Chuck Lidell (10), and Anthony Johnson (12).
Among the women, Amanda Nunes has five knockout wins via punches. She is also tied with Stipe Miocic in third place among UFC champions who won title fights with a knockout - both with four wins each.