| Final 19:58 | team | time | +time | L |   |  | 1. Matthew Grevers |  USA | 52.16s | OR | 04 |  Stats |  | 2. Nick Thoman |  USA | 52.92s | +0.76s | 02 |  Stats |  | 3. Ryosuke Irie |  JPN | 52.97s | +0.81s | 06 |  Stats |  | 4. Camille Lacourt |  FRA | 53.08s | +0.92s | 05 |  Stats |  | 5. Liam Tancock |  GBR | 53.35s | +1.19s | 03 |  Stats |  | 6. Helge Meeuw |  GER | 53.48s | +1.32s | 01 |  Stats |  | 7. Hayden Stoeckel |  AUS | 53.55s | +1.39s | 08 |  Stats |  | 8. Feiyi Cheng |  CHN | 53.77s | +1.61s | 07 |  Stats |   
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   |  | Matthew Grevers |   
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| Semi 1 | time | +time | L | Rk. |   |  | 1. Camille Lacourt |  FRA | 53.03s | - | 05 | 2. |  Times |  | 2. Liam Tancock |  GBR | 53.25s | +0.22s | 06 | 3. |  Times |  | 3. Feiyi Cheng |  CHN | 53.50s | +0.47s | 04 | 6. |  Times |  | 4. Arkady Vyatchanin |  RUS | 53.79s | +0.76s | 02 | 9. |  Times |  | 5. Nick Driebergen |  NED | 53.81s | +0.78s | 03 | 10. |  Times |  | 6. Aristeidis Grigoriadis |  GRE | 54.20s | +1.17s | 08 | 14. |  Times |  | 7. Charles Francis |  CAN | 54.42s | +1.39s | 07 | 15. |  Times |  | 8. Daniel Arnamnart |  AUS | 54.48s | +1.45s | 01 | 16. |  Times |   
| Semi 2 | time | +time | L | Rk. |   |  | 1. Matthew Grevers |  USA | 52.66s | - | 04 | 1. |  Times |  | 2. Ryosuke Irie |  JPN | 53.29s | +0.63 | 03 | 4. |  Times |  | 3. Nick Thoman |  USA | 53.47s | +0.81s | 05 | 5. |  Times |  | 4. Helge Meeuw |  GER | 53.52s | +0.86s | 06 | 7. |  Times |  | 5. Hayden Stoeckel |  AUS | 53.74s | +1.08s | 02 | 8. |  Times |  | 6. Jan-Philip Glania |  GER | 53.90s | +1.24s | 07 | 11. |  Times |  | 7. Aschwin Wildeboer Faber |  ESP | 53.99s | +1.33s | 08 | 12. |  Times |  | 8. Gareth Kean |  NZL | 54.00s | +1.34s | 01 | 13. |  Times |   
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|   | S | F |  | Semi 1 |   | 3  |  | Semi 2 |   | 5  |  | Heat 6 | 7 | 4 |  | Heat 5 | 5 | 2 |  | Heat 4 | 4 | 2 |  | Heat 3 |  | Heat 2  |  | Heat 1  |   
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| Heat 6 | time | +time | L | Rk. |   |  | 1. Matthew Grevers |  USA | 52.92s | - | 04 | 1. |  Times |  | 2. Feiyi Cheng |  CHN | 53.22s | +0.30s | 02 | 2. |  Times |  | 3. Ryosuke Irie |  JPN | 53.56s | +0.64s | 05 | 5. |  Times |  | 4. Nick Driebergen |  NED | 53.62s | +0.70s | 07 | 6. |  Times |  | 5. Hayden Stoeckel |  AUS | 53.88s | +0.96s | 06 | 9. |  Times |  | 6. Gareth Kean |  AUS | 54.26s | +1.34s | 03 | 14. |  Times |  | 7. Daniel Arnamnart |  NZL | 54.28s | +1.36s | 01 | 15. |  Times |  | 8. Charl Crous |  RSA | 55.37s | +2.45s | 08 | 32. |  Times |   
| Heat 5 | time | +time | L | Rk. |   |  | 1. Camille Lacourt |  FRA | 53.51s | - | 04 | 4. |  Times |  | 2. Liam Tancock |  GBR | 53.86s | +0.35s | 05 | 8. |  Times |  | 3. Arkady Vyatchanin |  RUS | 54.01s | +0.50s | 02 | 10. |  Times |  | 4. Jan-Philip Glania |  GER | 54.07s | +0.56s | 03 | 12. |  Times |  | 5. Charles Francis |  CAN | 54.08s | +0.57s | 08 | 13. |  Times |  | 6. Aristeidis Grigoriadis |  GRE | 54.52s | +1.01s | 06 | 17. |  Times |  | 7. Marcin Tarczynski |  POL | 55.06s | +1.55s | 01 | 27. |  Times |  | 8. Benjamin Stasiulis |  FRA | 55.36s | +1.85s | 07 | 31. |  Times |   
| Heat 4 | time | +time | L | Rk. |   |  | 1. Nick Thoman |  USA | 53.48s | - | 04 | 3. |  Times |  | 2. Helge Meeuw |  GER | 53.83s | +0.35s | 05 | 7. |  Times |  | 3. Vladimir Morozov |  RUS | 54.01s | +0.53s | 02 | 10. |  Times |  | 4. Aschwin Wildeboer Faber |  ESP | 54.36s | +0.88s | 03 | 16. |  Times |  | 5. Bastiaan Lijesen |  NED | 54.88s | +1.40s | 06 | 23. |  Times |  | 6. Yakov Toumarkin |  ISR | 54.91s | +1.43s | 01 | 24. |  Times |  | 7. Juan Miguel Rando Galvez |  ESP | 54.93s | +1.45s | 07 | 25. |  Times |  | 8. Daniel Orzechowski |  BRA | 55.16s | +1.68s | 08 | 28. |  Times |   
| Heat 3 | time | +time | L | Rk. |   |  | 1. Pavel Sankovich |  BLR | 54.53s | - | 01 | 18. |  Times |  | 2. Mirco di Tora |  ITA | 54.70s | +0.17s | 05 | 19. |  Times |  | 3. Chris Walker-Hebborn |  GBR | 54.78s | +0.25s | 07 | 20. |  Times |  | 4. Jianbin He |  CHN | 54.81s | +0.28s | 04 | 21. |  Times |  | 5. Richard Bohus |  HUN | 54.84s | +0.31s | 03 | 22. |  Times |  | 6. Lavrans Solli |  NOR | 55.00s | +0.47s | 08 | 26. |  Times |  | 7. Mathias Gydesen |  DEN | 55.31s | +0.78s | 02 | 30. |  Times |  | 8. Daniel Bell |  NZL | 55.53s | +1.00s | 06 | 37. |  Times |   
| Heat 2 | time | +time | L | Rk. |   |  | 1. George Richard Bovell |  TRI | 55.22s | - | 08 | 29. |  Times |  | 2. Omar Pinzon Garcia |  COL | 55.37s | +0.15s | 05 | 32. |  Times |  | 3. Pedro Medel |  CUB | 55.40s | +0.18s | 01 | 34. |  Times |  | 4. Oleksandr Isakov |  UKR | 55.43s | +0.21s | 02 | 35. |  Times |  | 5. Seonkwan Park |  KOR | 55.51s | +0.29s | 07 | 36. |  Times |  | 6. Alexandr Tarabrin |  KAZ | 55.55s | +0.33s | 04 | 38. |  Times |  | 7. Gede Sudartawa I |  INA | 55.99s | +0.77s | 06 | 39. |  Times |  | 8. Federico Grabich |  ARG | 56.56s | +1.34s | 03 | 41. |  Times |   
| Heat 1 | time | +time | L | Rk. |   |  | 1. Bradley Ally |  BAR | 56.27s | - | 04s | 40. |  Times |  | 2. Heshan Unamboowe |  SRI | 57.94s | +1.67 | 05s | 42. |  Times |  | 3. Zane Jordan |  ZAM | 58.77s | +2.50 | 03s | 43. |  Times |   
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| Total eligible to participate 45 swimmers (started 43) |   
|  Olympic Qualifying Time – 54.40s 24+7 |  | Hayden Stoeckel | AUS | 7. | Daniel Arnamnart | AUS | 16. |  | Daniel Orzechowski | BRA | 28. | Thiago Pereira | BRA | DNS |  | Cheng Feiyi | CHN | 8. | He Jianbin | CHN | 21. |  | Camille Lacourt | FRA | 4. | Benjamin Stasiulis | FRA | 31. |  | Liam Tancock | GBR | 5. | Chris Walker-Hebborn | GBR | 20. |  | Jan Philip Glania | GER | 11. | Helge Meeuw | GER | 6. |  | Nick Driebergen | NED | 10. | Bastiaan Lijesen | NED | 23. |  | Gareth Kean | NZL | 13. | Daniel Bell | NZL | 37. |  | Arkady Vyatchanin | RUS | 9. | Vladimir Morozov | RUS |  | Aschwin Wildeboer Faber | ESP | 12. | Juan Miguel Rando | ESP | 25. |  | Matt Grevers | USA | 1. | Nick Thoman | USA | 2. |  | Yakov-Yan Toumarkin | ISR | 24. | Jonatan Kopelev | ISR |   |  | Charles Francis | CAN | 15. |  | Aristeidis Grigoriadis | GRE | 17. |  | Richard Bohus | HUN | 22. |  | Mirco Di Tora | ITA | 19. |  | Ryosuke Irie | JPN | 3. |  | Marcin Tarczyński | POL | 27. |  | Charl Crous | RSA | 32. |   
 Jonatan Kopelev (ISR) underwent an appendectomy on July, 15th and missed the Games.  
 
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|  Olympic Selection Time - 56.30s - 12 |  | Matthias Gydesen | DEN | 54.41s | 30. |  | Pavel Sankovich | BLR | 54.56s | 18. |  | Lavrans Solli | NOR | 54.83s | 26. |  | Aleksandr Tarabrin | KAZ | 54.85s | 38. |  | Omar Andres Pinzón | COL | qoe | 32. |  | Federico Grabich | ARG | 55.22s | 41. |  | Gede Siman Sudartawa I | INA | 55.32s | 39. |  | Oleksandr Isakov | UKR | 55.33s | 35. |  | Park Seon-Kwan | KOR | 55.39s | 36. |  | Pedro Medel | CUB | 55.63s | 34. |  | George Bovell | TRI | qoe | 29. |  | Bradley Ally | BAR | qoe | 40. |   
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|  Wildcard Places - 2 |  | Heshan Unamboowe | SRI | 42. |  | Zane Jordan | ZAM | 43. |   
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| Olympic Qualification time | time | place | date | birth |  | 1. Matt Grevers | USA | 52.08s | Omaha(USA) | 25.06.2012 | 26/03/1985 |  | 2. Camille Lacourt | FRA | 52.44s | Strasburg(FRA) | 23.03.2011 | 22/04/1985 |  | 3. Nick Thoman | USA | 52.86s | Omaha(USA) | 25.06.2012 | 06/03/1986 |  | 4. Ryosuke Irie | JPN | 52.91s | Tokyo(JPN) | 02.04.2012 | 24/01/1990 |  | 5. Liam Tancock | GBR | 53.16s | London(GBR) | 03.03.2012 | 07/05/1985 |  | 6. Helge Meeuw | GER | 53.22s | Shanghai(CHN) | 24.07.2011 | 29/08/1984 |  | 7. Gareth Kean | NZL | 53.32s | Auckland(NZL) | 25.03.2012 | 05/10/1991 |  | 8. Jan-Philip Glania | GER | 53.50s | Berlin(GER) | 10.05.2012 | 08/11/1988 |  | 9. Aschwin Wildeboer Faber | ESP | 53.67s | Roma(ITA) | 17.06.2011 | 14/02/1986 |  | 10 Hayden Stoeckel | AUS | 53.70s | Shanghai(CHN) | 24.07.2011 | 10/08/1984 |  | 11.Thiago Pereira | BRA | 53.86s | Rio de Janeiro(BRA) | 24.04.2012 | 26/01/1986 |  | 12.Aristeidis Grigoriadis | GRE | 53.86s | Debrecen(HUN) | 21.05.2012 | 06/12/1985 |  | 13.Bastiaan Lijesen | NED | 53.86s | Eindhoven(NED) | 12.04.2012 | 28/12/1990 |  | 14.Feiyi Cheng | CHN | 53.87s | Shaoxing(CHN) | 01.04.2012 | 06/01/1991 |  | 15.Arkady Vyatchanin | RUS | 53.91s | Moscow(RUS) | 17.04.2012 | 04/04/1984 |  | 16.Vladimir Morozov | RUS | 53.93s | Moscow(RUS) | 17.04.2012 | 16/06/1992 |  | 17.Benjamin Stasiulis | FRA | 53.98s | Dunkerke(FRA) | 18.03.2012 | 20/07/1986 |  | 18.Nick Driebergen | NED | 53.98s | Shanghai(CHN) | 24.07.2011 | 19/08/1987 |  | 19.Juan Rando Galvez | ESP | 54.04s | Malaga(ESP) | 29.03.2012 | 26/03/1988 |  | 20.Daniel Arnamnart | AUS | 54.05s | Adelaide(AUS) | 15.03.2012 | 14/09/1989 |  | 21.Marcin Tarczynski | POL | 54.12s | Olsztyn(POL) | 12.05.2012 | 10/09/1990 |  | 22.Yakov Toumarkin | ISR | 54.14s | Debrecen(HUN) | 21.05.2012 | 15/02/1992 |  | 23.Charl Crous | RSA | 54.17s | Durban(RSA) | 16.04.2012 | 25/09/1990 |  | 24.Charles Francis | CAN | 54.19s | Shanghai(CHN) | 24.07.2011 | 17/08/1988 |  | 25.Daniel Orzechowski | BRA | 54.20s | Rio de Janeiro(BRA) | 24.04.2012 | 01/08/1985 |  | 26.Jianbin He | CHN | 54.25s | Shaoxing(CHN) | 01.04.2012 | 18/02/1993 |  | 27.Chris Walker-Hebborn | GBR | 54.26s | Sheffield(GBR) | 22.06.2012 | 01/07/1990 |  | 28.Mirco Di Tora | ITA | 54.27s | Riccione(ITA) | 13.04.2011 | 19/05/1986 |  | 29.Richard Bohus | HUN | 54.35s | Debrecen(HUN) | 21.05.2012 | 09/04/1993 |  | 30.Jonatan Kopelev | ISR | 54.38s | Kranj(SLO) | 02.06.2012 | 01/10/1991 |  | 31.Daniel Bell | NZL | 54.39s | Auckland(NZL) | 25.03.2012 | 09/05/1990 |   
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