| Order / Lane | Bib | ATHLETE | COUNTRY | PB | SB 2023 | 
|---|---|---|---|---|---|
| 2 | 2646 | Michael JOSEPH |  LCA | 44.77 | 44.77 | 
| 3 | 2101 | Leungo SCOTCH |  BOT | 44.82 | 44.82 | 
| 4 | 2919 | Jereem RICHARDS |  TTO | 44.54 | 44.54 | 
| 5 | 2558 | Antonio WATSON |  JAM | 44.54 | 44.54 | 
| 6 | 2589 | Kentaro SATO |  JPN | 44.77 | 44.77 | 
| 7 | 3018 | Vernon NORWOOD |  USA | 44.35 | 44.39 | 
| 8 | 2842 | Wayde VAN NIEKERK |  RSA | 43.03 | 44.08 | 
| 9 | 2431 | Attila MOLNÁR |  HUN | 44.84 | 44.84 | 
| Order / Lane | Bib | ATHLETE | COUNTRY | PB | SB 2023 | 
|---|---|---|---|---|---|
| 2 | 2097 | Busang Collen KEBINATSHIPI |  BOT | 44.80 | 44.80 | 
| 3 | 2073 | Dylan BORLÉE |  BEL | 45.09 | 45.09 | 
| 4 | 2699 | Liemarvin BONEVACIA |  NED | 44.48 | 44.78 | 
| 5 | 2413 | Kirani JAMES |  GRN | 43.74 | 44.50 | 
| 6 | 2588 | Fuga SATO |  JPN | 44.97 | 44.97 | 
| 7 | 2349 | Matthew HUDSON-SMITH |  GBR | 44.35 | 44.69 | 
| 8 | 2731 | Håvard Bentdal INGVALDSEN |  NOR | 44.39 | 44.39 | 
| 9 | 2530 | Zandrion BARNES |  JAM | 44.90 | 44.90 | 
| Order / Lane | Bib | ATHLETE | COUNTRY | PB | SB 2023 | 
|---|---|---|---|---|---|
| 2 | 2833 | Zakithi NENE |  RSA | 44.74 | 44.74 | 
| 3 | 2511 | Davide RE |  ITA | 44.77 | 45.07 | 
| 4 | 2529 | Sean BAILEY |  JAM | 44.43 | 44.43 | 
| 5 | 2079 | Alexander DOOM |  BEL | 44.92 | 44.92 | 
| 6 | 2060 | Steven GARDINER |  BAH | 43.48 | 43.74 | 
| 7 | 2989 | Quincy HALL |  USA | 44.41 | 44.41 | 
| 8 | 2099 | Bayapo NDORI |  BOT | 44.61 | 44.61 | 
| 9 | 2582 | Yuki Joseph NAKAJIMA |  JPN | 45.12 | 45.12 |