Sorted alphabetically by last name · 2769 fighters
| Name | Nickname | |
|---|---|---|
| KS | Kody Steele | |
| KK | Koji Kitao | |
| KO | Koji Oishi | |
| KE | Konstantin Erokhin | |
| KM | Kris McCray | "Savage" |
| KM | Kris Moutinho | |
| KR | Kristian Rothaermel | |
| KM | Kristof Midoux |
| "The Hurricane" |
| KG | Kron Gracie |
| KJ | Krzysztof Jotko |