| POS | Rank | Heat | BIB | ATHLETE | COUNTRY | RESULTS | ms* | 
|---|---|---|---|---|---|---|---|
| 1 | 1 | 5 | 2417 | Khallifah ROSSER | 
 USA                 | 
                48.62 Q | |
| 2 | 1 | 4 | 1785 | Rasmus MÄGI | 
 EST                 | 
                48.78 Q | |
| 3 | 1 | 1 | 2357 | Rai BENJAMIN | 
 USA                 | 
                49.06 Q | |
| 4 | 2 | 4 | 1973 | Thomas BARR | 
 IRL                 | 
                49.15 Q SB | |
| 5 | 3 | 4 | 1699 | Gerald DRUMMOND | 
 CRC                 | 
                49.16 Q | |
| 6 | 4 | 4 | 2353 | Trevor BASSITT | 
 USA                 | 
                49.17 Q | |
| 7 | 1 | 3 | 2197 | Karsten WARHOLM | 
 NOR                 | 
                49.34 Q SB | |
| 8 | 5 | 4 | 1861 | Alastair CHALMERS | 
 GBR                 | 
                49.37 q | |
| 9 | 1 | 2 | 1611 | Alison DOS SANTOS | 
 BRA                 | 
                49.41 Q | |
| 10 | 2 | 2 | 2032 | Kemar MOWATT | 
 JAM                 | 
                49.44 Q | |
| 11 | 6 | 4 | 2037 | Shawn ROWE | 
 JAM                 | 
                49.51 q | |
| 12 | 2 | 1 | 1506 | Abdelmalik LAHOULOU | 
 ALG                 | 
                49.58 Q | |
| 13 | 3 | 2 | 1832 | Wilfried HAPPIO | 
 FRA                 | 
                49.60 Q | |
| 14 | 2 | 5 | 2157 | Ramsey ANGELA | 
 NED                 | 
                49.62 Q | |
| 15 | 3 | 5 | 2296 | Carl BENGTSTRÖM | 
 SWE                 | 
                49.64 Q | .640 | 
| 15 | 3 | 1 | 2179 | Ezekiel NATHANIEL | 
 NGR                 | 
                49.64 Q | .640 | 
| 17 | 4 | 2 | 2168 | Nick SMIDT | 
 NED                 | 
                49.80 Q | |
| 18 | 2 | 3 | 1586 | Julien WATRIN | 
 BEL                 | 
                49.83 Q | .822 | 
| 19 | 7 | 4 | 2327 | Yasmani COPELLO | 
 TUR                 | 
                49.83 q | .830 | 
| 20 | 4 | 5 | 2013 | Kyron MCMASTER | 
 IVB                 | 
                49.98 Q | |
| 21 | 4 | 1 | 2061 | Kazuki KUROKAWA | 
 JPN                 | 
                50.02 Q | |
| 22 | 3 | 3 | 2029 | Jaheel HYDE | 
 JAM                 | 
                50.03 Q | |
| 23 | 5 | 2 | 2272 | Sokwakhana ZAZINI | 
 RSA                 | 
                50.09 q | |
| 24 | 5 | 5 | 2000 | Mario LAMBRUGHI | 
 ITA                 | 
                50.18 | .175 | 
| 25 | 5 | 5 | 1754 | Pablo Andres IBAÑEZ GUEVARA | 
 ESA                 | 
                50.18 | .175 | 
| 26 | 4 | 3 | 2099 | Moitalel MPOKE | 
 KEN                 | 
                50.19 Q | |
| 27 | 5 | 1 | 2313 | Chieh CHEN | 
 TPE                 | 
                50.28 | |
| 28 | 5 | 3 | 2287 | Julien BONVIN | 
 SUI                 | 
                50.40 | |
| 29 | 6 | 2 | 2059 | Takayuki KISHIMOTO | 
 JPN                 | 
                50.66 | |
| 30 | 7 | 5 | 1717 | VÃt MÜLLER | 
 CZE                 | 
                50.71 | |
| 31 | 7 | 2 | 1958 | Jabir MADARI PALLIYALIL | 
 IND                 | 
                50.76 | |
| 32 | 6 | 1 | 1880 | Chris MCALISTER | 
 GBR                 | 
                51.55 | |
| 33 | 8 | 4 | 1630 | Mahau SUGUIMATI | 
 BRA                 | 
                52.43 | |
| 34 | 6 | 3 | 2276 | Ned AZEMIA | 
 SEY                 | 
                53.07 | |
| 35 | 7 | 3 | 1741 | Juander SANTOS | 
 DOM                 | 
                58.80 | |
| 1 | 1698 | Jordin ANDRADE | 
 CPV                 | 
                DNF | |||
| 1 | 2288 | Dany BRAND | 
 SUI                 | 
                DNS | 
ms - Milliseconds - shown when two or more competitors finish with the same time down to hundredths of a second