2018 FINA World Swimming Championships (25 m) – Men's 400 metre individual medley
The Men's 400 metre individual medley competition of the 2018 FINA World Swimming Championships was held on 15 December 2018.
Records
Prior to the competition, the existing world and championship records were as follows.| Name | Nation | Time | Location | Date | |
| World record Championship record | Ryan Lochte | 3:55.50 | Dubai | 16 December 2010 |
Results
Heats
The heats were started at 9:56.| Rank | Heat | Lane | Name | Nationality | Time | Notes |
| 1 | 4 | 5 | Daiya Seto | 4:00.50 | Q | |
| 2 | 3 | 2 | Brandonn Almeida | 4:04.58 | Q | |
| 3 | 2 | 3 | Tomas Peribonio | 4:05.08 | Q | |
| 3 | 4 | 3 | Thomas Fraser-Holmes | 4:05.08 | Q | |
| 5 | 4 | 6 | Tomoya Takeuchi | 4:05.21 | Q | |
| 6 | 4 | 4 | Péter Bernek | 4:05.49 | Q | |
| 7 | 3 | 5 | Gergely Gyurta | 4:06.13 | Q | |
| 8 | 3 | 8 | João Vital | 4:06.93 | Q | |
| 9 | 4 | 9 | Richard Nagy | 4:07.91 | ||
| 10 | 4 | 1 | Joan Lluís Pons | 4:08.33 | ||
| 11 | 3 | 6 | David Schlicht | 4:08.41 | ||
| 12 | 4 | 7 | Marc Sánchez | 4:08.51 | ||
| 13 | 2 | 6 | Kieran Smith | 4:08.52 | ||
| 14 | 2 | 2 | Mark Szaranek | 4:08.86 | ||
| 15 | 4 | 2 | Leonardo Coelho Santos | 4:08.93 | ||
| 16 | 3 | 3 | Daniil Pasynkov | 4:09.19 | ||
| 17 | 2 | 7 | Jarod Arroyo | 4:10.40 | ||
| 18 | 3 | 0 | Patrick Staber | 4:11.05 | ||
| 19 | 3 | 9 | Wang Hsing-Hao | 4:11.22 | ||
| 20 | 3 | 7 | Wang Yizhe | 4:11.64 | ||
| 21 | 4 | 8 | Tomoe Hvas | 4:12.56 | ||
| 22 | 4 | 0 | Ayrton Sweeney | 4:13.21 | ||
| 23 | 2 | 4 | Wilrich Coetzee | 4:13.81 | ||
| 24 | 3 | 1 | Adam Paulsson | 4:14.16 | ||
| 25 | 2 | 5 | Svetlozar Nikolov | 4:14.25 | ||
| 26 | 1 | 5 | Brandon Schuster | 4:17.20 | ||
| 27 | 2 | 8 | Hưng Nguyên Tran | 4:17.92 | ||
| 28 | 2 | 0 | Luis Vega Torres | 4:19.27 | NR | |
| 29 | 2 | 9 | Erick Gordillo | 4:21.02 | ||
| 30 | 1 | 3 | Munzer Kabbara | 4:21.59 | ||
| 31 | 1 | 2 | Nichita Bortnicov | 4:23.08 | ||
| 32 | 1 | 4 | Malcolm Low | 4:25.31 | ||
| 33 | 2 | 1 | Alberto Batungbacal | 4:25.90 | ||
| 34 | 1 | 6 | Mathieu Marquet | 4:33.24 | ||
| 3 | 4 | Wang Shun | DNS |
Final
The final was held on 15 December at 20:22.| Rank | Lane | Name | Nationality | Time | Notes |
| 4 | Daiya Seto | 3:56.43 | |||
| 6 | Thomas Fraser-Holmes | 4:02.74 | |||
| 5 | Brandonn Almeida | 4:03.71 | |||
| 4 | 7 | Péter Bernek | 4:04.71 | ||
| 5 | 1 | Gergely Gyurta | 4:04.74 | ||
| 6 | 3 | Tomas Peribonio | 4:06.26 | ||
| 7 | 2 | Tomoya Takeuchi | 4:06.99 | ||
| 8 | 8 | João Vital | 4:07.69 |