Best Times for Places in the Olympics
| POSITION | BEST TIME | PREVIOUS BEST TIME |
| 1st | 43.03 Wayne Van Niekerk (RSA), 2016, Rio de Janeiro, Brazil | 43.49, Michael Johnson (USA), 1996, Atlanta, USA |
| 2nd | 43.76 Kirani James (Grenada), 2016, Rio de Janeiro, Brazil | 43.93 Butch Reynolds (USA), 1996, Atlanta, USA |
| 3rd | 43.85 La Shawn Merritt (USA), 2016, Rio de Janeiro, Brazil | 44.09 Danny Everett (USA, 1988, Seoul, South Korea |
| 4th | 44.01, Machel Cedenio (TTO), 2016, Rio de Janeiro, Brazil | 44.25, Ian Morris (TTO), 1992, Barcelona, Spain |
| 5th | 44.25 Karabo Sibanda (BOT), 2016, Rio de Janeiro, Brazil | 44.52, Roberto Hernandez (CUB),1992, Barcelona, Spain |
| 6th | 44.36 Ali Khamis Khamis (BRN), 2016, Rio de Janeiro, Brazil | 44.75, Robert Grindley (GBR), 1992, Barcelona, Spain |
| 7th | 44.45 Bralon Taplin (GRN), 2016, Rio de Janeiro, Brazil | 44.94 Leslie Djhone, France, 2004, Athens, Greece |
| 8th | 44.61 Michael Hudson-Smith, 2016, Rio de Janeiro, Brazil | 45.03, Mohammed Al-Malky (OMA), 1988,
Seoul, South Korea |
Best Mark for Places-All Competitions
| POSITION | BEST TIME | PREVIOUS BEST TIME |
| 1st | 43.03 Wayne Van Niekirk (RSA), 2016 Olympics, Rio de Janeiro, Brazil | 43.18, Michael Johnson (USA), 1999 World Championships |
| 2nd | 43.65 La Shawn Merritt (USA
2015 World Championships, Beijing, China |
|
| 3rd | 43.78 Kirani James (GRN)
2015 World Championships Beijing, China |
|
| 4th | 44.01, Machel Cedenio (TTO), 2016 Olympics, Rio de Janeiro, Brazil | 44.11, Luguelin Santos (DOM), 2015 World Championships, Beijing, China |
| 5th | 44.25 Karabo Sibanda (BOT), 2016 Olympics, Rio de Janeiro, Brazil | 44.45 Antonio Pettigrew (USA), 1993 US Championships |
| 6th | 44.36 Ali Khamis Khamis (BRN), 2016 Olympics, Rio de Janeiro, Brazil | 44.52 Iwan Thomas (GBR),
1997 World Championships, Athens, Greece |
| 7th | 44.45 Bralon Taplin (GRN),
2016 Olympics, Rio de Janeiro, Brazil |
44.72 Johan Wissman (SWE),
2007 World Championships, Osaka, Japan |
| 8th | 44.61 Michael Hudson-Smith, 2016, Rio de Janeiro, Brazil | 44.92 Samson Kitur (KEN),
1993 Zurich Weltklasse, Switzerland, |