| First | Last | Nickname | Ht. | Wt. | Reach | Stance | W | L | D | Belt |
|---|---|---|---|---|---|---|---|---|---|---|
| Patrick | Kaase | Kamikaze | 5' 9" | 185 lbs. | -- | 1 | 2 | 0 | ||
| Emily | Peters Kagan | 5' 3" | 115 lbs. | 66.0" | 3 | 3 | 0 | |||
| Sirwan | Kakai | Zohan | 5' 5" | 135 lbs. | 66.0" | Orthodox | 12 | 3 | 0 | |
| Geza | Kalman | 6' 1" | 200 lbs. | -- | 4 | 9 | 0 | |||
| Bryson | Kamaka | 5' 11" | 170 lbs. | -- | Orthodox | 12 | 18 | 1 | ||
| Martin | Kampmann | The Hitman | 6' 0" | 170 lbs. | 72.0" | Orthodox | 20 | 7 | 0 | |
| Bharat | Kandare | Daring | 5' 7" | 135 lbs. | 72.0" | Orthodox | 5 | 3 | 0 | |
| Hiromitsu | Kanehara | 5' 10" | 200 lbs. | -- | Orthodox | 19 | 24 | 3 | ||
| Masanori | Kanehara | 5' 7" | 135 lbs. | 67.0" | Orthodox | 25 | 13 | 5 | ||
| Ken | Kaneko | 6' 0" | 161 lbs. | -- | Orthodox | 0 | 3 | 0 | ||
| Denis | Kang | 5' 11" | 185 lbs. | 77.0" | Orthodox | 34 | 15 | 2 | ||
| Kyung Ho | Kang | Mr. Perfect | 5' 9" | 135 lbs. | 73.0" | Orthodox | 15 | 8 | 0 | |
| David | Kaplan | Diamond | 5' 7" | 155 lbs. | -- | Orthodox | 3 | 4 | 0 | |
| Kai | Kara-France | Don't Blink | 5' 5" | 125 lbs. | 69.0" | Orthodox | 19 | 7 | 0 | |
| Georgi | Karakhanyan | Insane | 5' 8" | 145 lbs. | -- | 24 | 4 | 1 | ||
| Alex | Karalexis | The Assassin | 5' 8" | 155 lbs. | 66.0" | Orthodox | 10 | 6 | 0 | |
| Nadia | Kassem | 187 | 5' 5" | 125 lbs. | 66.0" | Southpaw | 5 | 1 | 0 | |
| Yusuke | Kasuya | 5' 7" | 155 lbs. | 67.0" | Southpaw | 9 | 3 | 2 | ||
| Tetsuji | Kato | -- | 155 lbs. | -- | Orthodox | 20 | 10 | 0 | ||
| Hisaki | Kato | 6' 0" | 185 lbs. | -- | 8 | 2 | 0 | |||
| Brad | Katona | Superman | 5' 6" | 135 lbs. | 65.0" | Orthodox | 9 | 0 | 0 | |
| Calvin | Kattar | The Boston Finisher | 5' 11" | 145 lbs. | 72.0" | Orthodox | 19 | 3 | 0 | |
| Sarah | Kaufman | 5' 5" | 135 lbs. | 67.0" | Orthodox | 17 | 4 | 0 | ||
| Yusuke | Kawaguchi | 6' 0" | 255 lbs. | -- | 13 | 4 | 0 | |||
| Canaan | Kawaihae | 6' 0" | 145 lbs. | -- | Southpaw | 4 | 1 | 0 |