| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 3086 | Karsten WARHOLM |  NOR | 47.30 Q | 0.156 | 
| 2 | 3907 | Rai BENJAMIN |  USA | 47.37 Q | 0.184 | 
| 3 | 3668 | Yasmani COPELLO |  TUR | 47.88 q SB | 0.183 | 
| 4 | 2341 | Thomas BARR |  IRL | 48.26 SB | 0.151 | 
| 5 | 2611 | Kemar MOWATT |  JAM | 48.95 | 0.166 | 
| 6 | 3444 | Sokwakhana ZAZINI |  RSA | 48.99 SB | 0.150 | 
| 7 | 1979 | Ludvy VAILLANT |  FRA | 49.02 SB | 0.162 | 
| 8 | 2145 | Joshua ABUAKU |  GER | 49.93 | 0.179 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 1318 | Alison DOS SANTOS |  BRA | 47.31 Q AR | 0.171 | 
| 2 | 3295 | Abderrahman Almoubarrake S ALSALECK |  QAT | 47.47 Q SB | 0.188 | 
| 3 | 2439 | Alessandro SIBILIO |  ITA | 47.93 q PB | 0.123 | 
| 4 | 3968 | Kenneth SELMON |  USA | 48.58 | 0.225 | 
| 5 | 2154 | Luke CAMPBELL |  GER | 48.62 PB | 0.153 | 
| 6 | 2626 | Shawn ROWE |  JAM | 48.83 PB | 0.204 | 
| 7 | 3026 | Nick SMIDT |  NED | 49.35 SB | 0.164 | 
| 8 | 1637 | VÃt MÜLLER |  CZE | 49.69 | 0.145 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 2456 | Kyron MCMASTER |  IVB | 48.26 Q | 0.179 | 
| 2 | 1824 | Rasmus MÄGI |  EST | 48.36 Q NR | 0.156 | 
| 3 | 3939 | David KENDZIERA |  USA | 48.67 | 0.190 | 
| 4 | 2172 | Constantin PREIS |  GER | 49.10 | 0.186 | 
| 5 | 1008 | Abdelmalik LAHOULOU |  ALG | 49.14 | 0.125 | 
| 6 | 2724 | Hiromu YAMAUCHI |  JPN | 49.35 | 0.192 | 
| 7 | 1958 | Wilfried HAPPIO |  FRA | 49.49 | 0.130 | 
| 8 | 2592 | Jaheel HYDE |  JAM | 1:27.38 | 0.159 |