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
1 1 1 2410 Michael NORMAN USAUSA 44.30 Q
2 2 1 1874 Matthew HUDSON-SMITH GBRGBR 44.38 Q
3 1 3 2351 Champion ALLISON USAUSA 44.71 Q
4 1 2 1945 Kirani JAMES GRNGRN 44.74 Q
5 2 3 2268 Wayde VAN NIEKERK RSARSA 44.75 Q
6 3 3 1566 Jonathan JONES BARBAR 44.78 q
7 2 2 1595 Bayapo NDORI BOTBOT 44.94 Q
8 3 1 2041 Christopher TAYLOR JAMJAM 44.97 q SB
9 3 2 2437 Muzala SAMUKONGA ZAMZAM 45.02 PB
10 4 3 1872 Alex HAYDOCK-WILSON GBRGBR 45.08 PB
11 4 1 2264 Zakithi NENE RSARSA 45.24
12 5 3 1572 Kévin BORLÉE BELBEL 45.26
13 4 2 2366 Michael CHERRY USAUSA 45.28
14 5 1 1571 Dylan BORLÉE BELBEL 45.41
15 6 3 2159 Liemarvin BONEVACIA NEDNED 45.50
16 7 3 2080 Mikhail LITVIN KAZKAZ 45.63 SB
17 5 2 2069 Fuga SATO JPNJPN 45.71
18 6 1 2075 Julian Jrummi WALSH JPNJPN 45.75
19 6 2 1579 Alexander DOOM BELBEL 45.80
20 7 2 1979 Christopher O'DONNELL IRLIRL 46.01
21 8 3 1594 Isaac MAKWALA BOTBOT 46.04
22 7 1 1736 Lidio Andres FELIZ DOMDOM 46.19
23 8 1 1526 Alex BECK AUSAUS 46.21
2 2014 Nathon ALLEN JAMJAM DNF