| POS | Rank | Heat | BIB | ATHLETE | COUNTRY | RESULTS | ms* | 
|---|---|---|---|---|---|---|---|
| 1 | 1 | 2 | 400 | Bryce HOPPEL | 
 USA                 | 
                1:45.08 Q SB | .072 | 
| 2 | 2 | 2 | 119 | Eliott CRESTAN | 
 BEL                 | 
                1:45.08 Q PB | .076 | 
| 3 | 3 | 2 | 208 | Benjamin ROBERT | 
 FRA                 | 
                1:45.28 Q PB | |
| 4 | 4 | 2 | 280 | Abdelati EL GUESSE | 
 MAR                 | 
                1:45.45 | |
| 5 | 5 | 2 | 184 | Mohamed ATTAOUI | 
 ESP                 | 
                1:45.68 | |
| 6 | 1 | 1 | 186 | Mariano GARCÍA | 
 ESP                 | 
                1:47.83 Q | |
| 7 | 2 | 1 | 245 | Catalin TECUCEANU | 
 ITA                 | 
                1:48.13 Q | |
| 8 | 3 | 1 | 368 | Andreas KRAMER | 
 SWE                 | 
                1:48.14 Q | |
| 9 | 4 | 1 | 397 | Isaiah HARRIS | 
 USA                 | 
                1:48.18 | |
| 10 | 5 | 1 | 129 | Tshepiso MASALELA | 
 BOT                 | 
                1:48.44 | |
| 11 | 6 | 1 | 120 | Tibo DE SMET | 
 BEL                 | 
                1:48.47 | |
| 2 | 103 | Mohamed Ali GOUANED | 
 ALG                 | 
                DNF | 
ms - Milliseconds - shown when two or more competitors finish with the same time down to hundredths of a second