First 2 in each heat (Q) and the next 2 fastest (q)

First 2 of each heat (Q) plus 2 fastest times (q) qualify to Final

POS Rank Heat BIB ATHLETE COUNTRY RESULTS ms*
1 1 1 2558 Antonio WATSON JAMJAM 44.13 Q PB
2 1 2 2349 Matthew HUDSON-SMITH GBRGBR 44.26 Q AR .253
3 2 1 3018 Vernon NORWOOD USAUSA 44.26 Q PB .258
4 1 3 2989 Quincy HALL USAUSA 44.43 Q
5 2 2 2413 Kirani JAMES GRNGRN 44.58 Q
6 3 1 2842 Wayde VAN NIEKERK RSARSA 44.65 q
7 3 2 2731 Håvard Bentdal INGVALDSEN NORNOR 44.70 q
8 4 1 2919 Jereem RICHARDS TTOTTO 44.76
9 4 2 2588 Fuga SATO JPNJPN 44.88 PB
10 2 3 2529 Sean BAILEY JAMJAM 44.94 Q
11 5 1 2589 Kentaro SATO JPNJPN 44.99
12 6 1 2431 Attila MOLNÁR HUNHUN 45.02
13 3 3 2582 Yuki Joseph NAKAJIMA JPNJPN 45.04 PB
14 5 2 2699 Liemarvin BONEVACIA NEDNED 45.23
15 4 3 2511 Davide RE ITAITA 45.29
16 6 2 2530 Zandrion BARNES JAMJAM 45.38
17 7 1 2646 Michael JOSEPH LCALCA 45.50
18 5 3 2079 Alexander DOOM BELBEL 45.57
19 7 2 2073 Dylan BORLÉE BELBEL 45.59
20 6 3 2833 Zakithi NENE RSARSA 45.64
21 8 1 2101 Leungo SCOTCH BOTBOT 45.96
22 8 2 2097 Busang Collen KEBINATSHIPI BOTBOT 46.39
3 2060 Steven GARDINER BAHBAH DNF
3 2099 Bayapo NDORI BOTBOT DNF
Legend

ms - Milliseconds - shown when two or more competitors finish with the same time down to hundredths of a second