The fastest knockout in UFC heavyweight history is Todd Duffee vs Tim Hague, at 7 seconds, at UFC 102: Couture vs Nogueira on 29 August 2009.
| # | Time | Bout | Result | Ended | Date | Event |
|---|---|---|---|---|---|---|
| 1 | 0:07 | Todd Duffee vs Tim Hague | Todd Duffee · KO/TKO | R1 0:07 | 2009-08-29 | UFC 102: Couture vs Nogueira |
| 2 | 0:09 | Allen Crowder vs Jairzinho Rozenstruik | Jairzinho Rozenstruik · KO/TKO | R1 0:09 | 2019-06-22 | UFC Fight Night: Moicano vs. The Korean Zombie |
| 3 | 0:12 | Aleksei Oleinik vs Walt Harris | Walt Harris · KO/TKO | R1 0:12 | 2019-07-20 | UFC Fight Night: Dos Anjos vs. Edwards |
| 4 | 0:12 | Gable Steveson vs Sean Sharafgraded call | Sean Sharaf · KO/TKO | R1 0:12 | 2026-09-19 | UFC 331: Van vs. Pantoja 2 |
| 5 | 0:14 | Anthony Hamilton vs Damian Grabowski | Anthony Hamilton · KO/TKO | R1 0:14 | 2016-07-30 | UFC 201: Lawler vs. Woodley |
| 6 | 0:15 | Andrei Arlovski vs Paul Buentellotitle | Andrei Arlovski · KO/TKO | R1 0:15 | 2005-10-07 | UFC 55: Fury |
| 7 | 0:15 | Curtis Blaydes vs Tom Aspinall | Curtis Blaydes · KO/TKO | R1 0:15 | 2022-07-23 | UFC Fight Night: Blaydes vs. Aspinall |
| 8 | 0:16 | Antonio Silva vs Stefan Struve | Stefan Struve · KO/TKO | R1 0:16 | 2016-05-08 | UFC Fight Night: Overeem vs Arlovski |
| 9 | 0:17 | Mark Kerr vs Greg Stott | Mark Kerr · KO/TKO | R1 0:17 | 1997-10-17 | UFC 15: Collision Course |
| 10 | 0:17 | Antoni Hardonk vs Colin Robinson | Antoni Hardonk · KO/TKO | R1 0:17 | 2008-01-19 | UFC 80: Rapid Fire |
| 11 | 0:17 | Gabriel Gonzaga vs Dave Herman | Gabriel Gonzaga · KO/TKO | R1 0:17 | 2013-07-06 | UFC 162: Silva vs Weidman |
| 12 | 0:18 | Robelis Despaigne vs Josh Parisian | Robelis Despaigne · KO/TKO | R1 0:18 | 2024-03-09 | UFC 299: O'Malley vs. Vera 2 |
| 13 | 0:19 | Matt Mitrione vs Philip De Fries | Matt Mitrione · KO/TKO | R1 0:19 | 2013-04-06 | UFC on FUEL TV: Mousasi vs Latifi |
| 14 | 0:20 | Marcos Rogerio de Lima vs Richardson Moreira | Marcos Rogerio de Lima · KO/TKO | R1 0:20 | 2014-05-31 | — |
| 15 | 0:20 | Francis Ngannou vs Jairzinho Rozenstruik | Francis Ngannou · KO/TKO | R1 0:20 | 2020-05-09 | UFC 249: Ferguson vs. Gaethje |
| 16 | 0:23 | Jairzinho Rozenstruik vs Chris Daukaus | Jairzinho Rozenstruik · KO/TKO | R1 0:23 | 2022-12-10 | UFC 282: Blachowicz vs. Ankalaev |
| 17 | 0:23 | Anthony Wint vs Lucas Armandgraded call | Anthony Wint · KO/TKO | R1 0:23 | 2026-10-03 | UFC 332: Silva vs. Wang |
| 18 | 0:24 | Anthony Hamilton vs Daniel Spitz | Daniel Spitz · KO/TKO | R1 0:24 | 2017-09-16 | UFC Fight Night: Rockhold vs. Branch |
| 19 | 0:25 | Walt Harris vs Nikita Krylov | Nikita Krylov · KO/TKO | R1 0:25 | 2014-01-25 | UFC on FOX: Henderson vs Thomson |
| 20 | 0:26 | Francis Ngannou vs Cain Velasquez | Francis Ngannou · KO/TKO | R1 0:26 | 2019-02-17 | UFC Fight Night: Ngannou vs. Velasquez |
| 21 | 0:28 | Ron Waterman vs Chris Condo | Ron Waterman · KO/TKO | R1 0:28 | 1999-05-07 | UFC 20: Battle for the Gold |
| 22 | 0:29 | Andrei Arlovski vs Jairzinho Rozenstruik | Jairzinho Rozenstruik · KO/TKO | R1 0:29 | 2019-11-02 | UFC 244: Masvidal vs. Diaz |
| 23 | 0:30 | Brad Kohler vs Steve Judson | Brad Kohler · KO/TKO | R1 0:30 | 1999-09-24 | UFC 22: Only One Can be Champion |
| 24 | 0:32 | Ben Rothwell vs Marcos Rogerio de Lima | Marcos Rogerio de Lima · KO/TKO | R1 0:32 | 2021-11-13 | UFC Fight Night: Holloway vs. Rodriguez |
| 25 | 0:33 | Todd Duffee vs Anthony Hamilton | Todd Duffee · KO/TKO | R1 0:33 | 2014-12-06 | UFC 181: Hendricks vs Lawler II |
| 26 | 0:33 | Derrick Lewis vs Marcos Rogerio de Lima | Derrick Lewis · KO/TKO | R1 0:33 | 2023-07-29 | UFC 291: Poirier vs. Gaethje 2 |
| 27 | 0:35 | Stipe Miocic vs Fabio Maldonado | Stipe Miocic · KO/TKO | R1 0:35 | 2014-05-31 | — |
| 28 | 0:35 | Justin Tafa vs Tallison Teixeira | Tallison Teixeira · KO/TKO | R1 0:35 | 2025-02-08 | UFC 312: Du Plessis vs. Strickland 2 |
| 29 | 0:35 | Derrick Lewis vs Tallison Teixeira | Derrick Lewis · KO/TKO | R1 0:35 | 2025-07-12 | UFC Fight Night: Lewis vs. Teixeira |
| 30 | 0:39 | Roy Nelson vs Stefan Struve | Roy Nelson · KO/TKO | R1 0:39 | 2010-03-31 | UFC Fight Night: Florian vs Gomi |
| 31 | 0:39 | Sergei Pavlovich vs Tallison Teixeiragraded call | Sergei Pavlovich · KO/TKO | R1 0:39 | 2026-05-30 | UFC Fight Night: Song vs. Figueiredo |
| 32 | 0:41 | Matt Mitrione vs Derrick Lewis | Matt Mitrione · KO/TKO | R1 0:41 | 2014-09-05 | UFC Fight Night: Jacare vs Mousasi |
| 33 | 0:43 | Vitor Belfort vs Scott Ferrozzo | Vitor Belfort · KO/TKO | R1 0:43 | 1997-02-07 | UFC 12: Judgement Day |
| 34 | 0:43 | David Abbott vs Hugo Duarte | David Abbott · KO/TKO | R1 0:43 | 1998-05-15 | UFC 17: Redemption |
| 35 | 0:43 | Gary Goodridge vs Andre Roberts | Gary Goodridge · KO/TKO | R1 0:43 | 1999-03-05 | UFC 19: Ultimate Young Guns |
| 36 | 0:43 | Stipe Miocic vs Philip De Fries | Stipe Miocic · KO/TKO | R1 0:43 | 2012-02-15 | UFC on FUEL TV: Sanchez vs Ellenberger |
| 37 | 0:44 | Shane Carwin vs Christian Wellisch | Shane Carwin · KO/TKO | R1 0:44 | 2008-05-24 | UFC 84: Ill Will |
| 38 | 0:45 | Curtis Blaydes vs Francis Ngannou | Francis Ngannou · KO/TKO | R1 0:45 | 2018-11-24 | UFC Fight Night: Blaydes vs. Ngannou 2 |
| 39 | 0:45 | Greg Hardy vs Juan Adams | Greg Hardy · KO/TKO | R1 0:45 | 2019-07-20 | UFC Fight Night: Dos Anjos vs. Edwards |
| 40 | 0:45 | Tom Aspinall vs Jake Collier | Tom Aspinall · KO/TKO | R1 0:45 | 2020-07-25 | UFC Fight Night: Whittaker vs. Till |
| 41 | 0:45 | Chris Daukaus vs Rodrigo Nascimento | Chris Daukaus · KO/TKO | R1 0:45 | 2020-10-10 | UFC Fight Night: Moraes vs. Sandhagen |
| 42 | 0:47 | Brendan Schaub vs Chase Gormley | Brendan Schaub · KO/TKO | R1 0:47 | 2010-03-21 | UFC Live: Vera vs Jones |
| 43 | 0:48 | Daniel Omielanczuk vs Chris de la Rocha | Daniel Omielanczuk · KO/TKO | R1 0:48 | 2015-07-18 | UFC Fight Night: Bisping vs Leites |
| 44 | 0:49 | Tai Tuivasa vs Harry Hunsucker | Tai Tuivasa · KO/TKO | R1 0:49 | 2021-03-20 | UFC Fight Night: Brunson vs. Holland |
| 45 | 0:50 | Walt Harris vs Serghei Spivac | Walt Harris · KO/TKO | R1 0:50 | 2019-05-04 | UFC Fight Night: Iaquinta vs. Cowboy |
| 46 | 0:51 | Roy Nelson vs Dave Herman | Roy Nelson · KO/TKO | R1 0:51 | 2012-05-26 | UFC 146: Dos Santos vs Mir |
| 47 | 0:52 | Vitor Belfort vs David Abbott | Vitor Belfort · KO/TKO | R1 0:52 | 1997-05-30 | UFC 13: The Ultimate Force |
| 48 | 0:54 | Junior Dos Santos vs Stefan Struve | Junior Dos Santos · KO/TKO | R1 0:54 | 2009-02-21 | UFC 95: Sanchez vs Stevenson |
| 49 | 0:54 | Stipe Miocic vs Andrei Arlovski | Stipe Miocic · KO/TKO | R1 0:54 | 2016-01-02 | UFC 195: Lawler vs Condit |
| 50 | 0:54 | Tai Tuivasa vs Sergei Pavlovich | Sergei Pavlovich · KO/TKO | R1 0:54 | 2022-12-03 | UFC Fight Night: Thompson vs. Holland |
| 51 | 0:55 | Derrick Lewis vs Sergei Pavlovich | Sergei Pavlovich · KO/TKO | R1 0:55 | 2022-07-30 | UFC 277: Pena vs. Nunes 2 |
| 52 | 0:56 | Josh Hokit vs Max Gimenis | Josh Hokit · KO/TKO | R1 0:56 | 2025-11-08 | UFC Fight Night: Bonfim vs. Brown |
| 53 | 0:59 | Pat Barry vs Shawn Jordan | Shawn Jordan · KO/TKO | R1 0:59 | 2013-06-15 | UFC 161: Evans vs Henderson |
| 54 | 0:59 | Marcin Tybura vs Augusto Sakai | Augusto Sakai · KO/TKO | R1 0:59 | 2019-09-14 | UFC Fight Night: Cowboy vs. Gaethje |
| 55 | 1:00 | Josh Barnett vs Travis Browne | Travis Browne · KO/TKO | R1 1:00 | 2013-12-28 | UFC 168: Weidman vs Silva 2 |
| 56 | 1:00 | Tom Aspinall vs Curtis Blaydestitle | Tom Aspinall · KO/TKO | R1 1:00 | 2024-07-27 | UFC 304: Edwards vs. Muhammad 2 |
| 57 | 1:01 | Gabriel Gonzaga vs Josh Hendricks | Gabriel Gonzaga · KO/TKO | R1 1:01 | 2008-11-15 | UFC 91: Couture vs Lesnar |
| 58 | 1:04 | Cain Velasquez vs Junior Dos Santostitle | Junior Dos Santos · KO/TKO | R1 1:04 | 2011-11-12 | UFC on FOX: Velasquez vs Dos Santos |
| 59 | 1:06 | Sergei Pavlovich vs Marcelo Golm | Sergei Pavlovich · KO/TKO | R1 1:06 | 2019-04-20 | UFC Fight Night: Overeem vs. Oleinik |
| 60 | 1:06 | Justin Tafa vs Parker Porter | Justin Tafa · KO/TKO | R1 1:06 | 2023-02-11 | UFC 284: Makhachev vs. Volkanovski |
| 61 | 1:07 | Brendan Schaub vs Chris Tuchscherer | Brendan Schaub · KO/TKO | R1 1:07 | 2010-07-03 | UFC 116: Lesnar vs Carwin |
| 62 | 1:07 | Tai Tuivasa vs Greg Hardy | Tai Tuivasa · KO/TKO | R1 1:07 | 2021-07-10 | UFC 264: Poirier vs. McGregor 3 |
| 63 | 1:09 | Brandon Vera vs Frank Mir | Brandon Vera · KO/TKO | R1 1:09 | 2006-11-18 | UFC 65: Bad Intentions |
| 64 | 1:09 | Shane Carwin vs Gabriel Gonzaga | Shane Carwin · KO/TKO | R1 1:09 | 2009-03-07 | UFC 96: Jackson vs Jardine |
| 65 | 1:09 | Sergei Pavlovich vs Tom Aspinalltitle | Tom Aspinall · KO/TKO | R1 1:09 | 2023-11-11 | UFC 295: Prochazka vs. Pereira |
| 66 | 1:10 | Brendan Schaub vs Ben Rothwell | Ben Rothwell · KO/TKO | R1 1:10 | 2012-04-21 | UFC 145: Jones vs Evans |
| 67 | 1:11 | Travis Browne vs Gabriel Gonzaga | Travis Browne · KO/TKO | R1 1:11 | 2013-04-13 | The Ultimate Fighter: Team Jones vs. Team Sonnen Finale |
| 68 | 1:11 | Francis Ngannou vs Junior Dos Santos | Francis Ngannou · KO/TKO | R1 1:11 | 2019-06-29 | UFC Fight Night: Ngannou vs. Dos Santos |
| 69 | 1:13 | Frank Mir vs Todd Duffee | Frank Mir · KO/TKO | R1 1:13 | 2015-07-15 | UFC Fight Night: Mir vs Duffee |
| 70 | 1:13 | Tom Aspinall vs Marcin Tybura | Tom Aspinall · KO/TKO | R1 1:13 | 2023-07-22 | UFC Fight Night: Aspinall vs. Tybura |
| 71 | 1:14 | Justin Eilers vs Mike Kyle | Justin Eilers · KO/TKO | R1 1:14 | 2004-08-21 | UFC 49: Unfinished Business |
| 72 | 1:17 | Vitor Belfort vs Tra Telligman | Vitor Belfort · KO/TKO | R1 1:17 | 1997-02-07 | UFC 12: Judgement Day |
| 73 | 1:18 | Andrei Arlovski vs Ian Freeman | Andrei Arlovski · KO/TKO | R1 1:18 | 2002-11-22 | UFC 40: Vendetta |
| 74 | 1:20 | Kennedy Nzechukwu vs Shamil Gazievgraded call | Shamil Gaziev · KO/TKO | R1 1:20 | 2026-08-22 | UFC Fight Night: Hernandez vs. Rodrigues |
| 75 | 1:21 | Junior Dos Santos vs Fabricio Werdum | Junior Dos Santos · KO/TKO | R1 1:21 | 2008-10-25 | UFC 90: Silva vs Cote |
| 76 | 1:21 | Cain Velasquez vs Antonio Silvatitle | Cain Velasquez · KO/TKO | R1 1:21 | 2013-05-25 | UFC 160: Velasquez vs Silva 2 |
| 77 | 1:22 | Justin Tafa vs Austen Lane | Justin Tafa · KO/TKO | R1 1:22 | 2023-09-09 | UFC 293: Adesanya vs. Strickland |
| 78 | 1:22 | Waldo Cortes Acosta vs Shamil Gaziev | Waldo Cortes Acosta · KO/TKO | R1 1:22 | 2025-11-22 | UFC Fight Night: Tsarukyan vs. Hooker |
| 79 | 1:24 | Chase Sherman vs Shamil Abdurakhimov | Shamil Abdurakhimov · KO/TKO | R1 1:24 | 2017-11-25 | UFC Fight Night: Bisping vs. Gastelum |
| 80 | 1:24 | Junior Tafa vs Parker Porter | Junior Tafa · KO/TKO | R1 1:24 | 2023-08-26 | UFC Fight Night: Holloway vs. The Korean Zombie |
| 81 | 1:25 | Brandon Vera vs Justin Eilers | Brandon Vera · KO/TKO | R1 1:25 | 2006-02-04 | UFC 57: Liddell vs Couture 3 |
| 82 | 1:26 | Ken Shamrock vs Kimo Leopoldo | Ken Shamrock · KO/TKO | R1 1:26 | 2004-06-19 | UFC 48: Payback |
| 83 | 1:28 | Ben Sosoli vs Marcos Rogerio de Lima | Marcos Rogerio de Lima · KO/TKO | R1 1:28 | 2020-02-22 | UFC Fight Night: Felder vs. Hooker |
| 84 | 1:31 | Shane Carwin vs Neil Wain | Shane Carwin · KO/TKO | R1 1:31 | 2008-10-18 | UFC 89: Bisping vs Leben |
| 85 | 1:32 | Andrei Arlovski vs Francis Ngannou | Francis Ngannou · KO/TKO | R1 1:32 | 2017-01-28 | UFC on FOX: Shevchenko vs. Pena |
| 86 | 1:33 | Pedro Rizzo vs Dan Severn | Pedro Rizzo · KO/TKO | R1 1:33 | 2000-09-22 | UFC 27: Ultimate Bad Boyz |
| 87 | 1:33 | Gabriel Gonzaga vs Shawn Jordan | Gabriel Gonzaga · KO/TKO | R1 1:33 | 2013-10-19 | UFC 166: Velasquez vs Dos Santos 3 |
| 88 | 1:34 | Francis Ngannou vs Bojan Mihajlovic | Francis Ngannou · KO/TKO | R1 1:34 | 2016-07-23 | UFC on FOX: Holm vs. Shevchenko |
| 89 | 1:35 | Tom Aspinall vs Alan Baudot | Tom Aspinall · KO/TKO | R1 1:35 | 2020-10-10 | UFC Fight Night: Moraes vs. Sandhagen |
| 90 | 1:40 | Antonio Silva vs Frank Mir | Frank Mir · KO/TKO | R1 1:40 | 2015-02-22 | UFC Fight Night: Bigfoot vs Mir |
| 91 | 1:40 | RJ Harris vs Alvin Hinesgraded call | RJ Harris · KO/TKO | R1 1:40 | 2026-07-18 | UFC Fight Night: Du Plessis vs. Usman |
| 92 | 1:42 | Alistair Overeem vs Francis Ngannou | Francis Ngannou · KO/TKO | R1 1:42 | 2017-12-02 | UFC 218: Holloway vs. Aldo 2 |
| 93 | 1:44 | Cyril Asker vs Walt Harris | Walt Harris · KO/TKO | R1 1:44 | 2017-06-17 | UFC Fight Night: Holm vs. Correia |
| 94 | 1:48 | Jon Madsen vs Gilbert Yvel | Jon Madsen · KO/TKO | R1 1:48 | 2010-10-23 | UFC 121: Lesnar vs Velasquez |
| 95 | 1:48 | Louie Sutherland vs Brando Pericicgraded call | Brando Pericic · KO/TKO | R1 1:48 | 2026-03-21 | UFC Fight Night: Evloev vs. Murphy |
| 96 | 1:53 | Justin Tafa vs Harry Hunsucker | Justin Tafa · KO/TKO | R1 1:53 | 2021-12-18 | UFC Fight Night: Lewis vs. Daukaus |
| 97 | 1:54 | Tim Sylvia vs Gan McGeetitle | Tim Sylvia · KO/TKO | R1 1:54 | 2003-09-26 | UFC 44: Undisputed |
| 98 | 1:55 | Mike Kyle vs James Irvin | Mike Kyle · KO/TKO | R1 1:55 | 2005-02-05 | UFC 51: Super Saturday |
| 99 | 1:55 | Aleksei Oleinik vs Chris Daukaus | Chris Daukaus · KO/TKO | R1 1:55 | 2021-02-20 | UFC Fight Night: Blaydes vs. Lewis |
| 100 | 1:55 | Brando Pericic vs Elisha Ellison | Brando Pericic · KO/TKO | R1 1:55 | 2025-09-27 | UFC Fight Night: Ulberg vs. Reyes |