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 3 1648 Delano KENNEDY JAMJAM 45.49 Q PB
2 1 1 1852 Lythe PILLAY RSARSA 45.61 Q SB
3 2 3 1986 Steven MCELROY USAUSA 45.67 Q
4 1 2 1270 Busang Collen KEBINATSHIPI BOTBOT 45.91 Q
5 2 1 1659 Shaemar UTER JAMJAM 45.96 Q PB
6 2 2 1924 Joshua ATKINSON THATHA 46.13 Q NU20R
7 3 1 1299 Yusuf Ali ABBAS BRNBRN 46.21 q
8 4 1 1314 Tyler FLOYD CANCAN 46.22 q PB
9 3 3 1319 Christopher MORALES-WILLIAMS CANCAN 46.27 PB
10 3 2 1995 Ashton SCHWARTZMAN USAUSA 46.50
11 5 1 1772 Andreas GRIMERUD NORNOR 46.54
12 4 3 1682 Masataka TOMODA JPNJPN 46.62
13 4 2 1369 Tadeáš PLAČEK CZECZE 46.63
14 5 2 1326 Martin KOUYOUMDJIAN CHICHI 46.69 PB
15 6 2 1411 Ángel GONZÁLEZ ESPESP 46.81
16 6 1 1408 Markel FERNANDEZ ESPESP 46.88
17 7 2 1241 Cooper SHERMAN AUSAUS 46.94 PB
18 5 3 1293 Vinícius MOURA BRABRA 47.00
19 6 3 1350 Marko OREŠKOVIĆ CROCRO 47.51
20 7 1 1717 Lukas SUTKUS LTULTU 47.55
21 7 3 1859 Tjaart VAN DER WALT RSARSA 47.69
22 8 1 1663 Shion ARITA JPNJPN 47.97
23 8 2 1689 Elkanah Kiprotich CHEMELILI KENKEN 48.03
24 8 3 1515 Lukas KRAPPE GERGER 48.10