Swimming at the 1948 Summer Olympics – Men's 400 metre freestyle
The men's 400 metre freestyle event at the 1948 Olympic Games took place between 31 July and 4 August at the Empire Pool. This swimming event used freestyle swimming, which means that the method of the stroke is not regulated. Nearly all swimmers use the front crawl or a variant of that stroke. Because an Olympic-size swimming pool is 50 metres long, this race consisted of eight lengths of the pool.Medalists
Results
Heats
| Rank | Athlete | Country | Time | Notes |
| 1 | Jimmy McLane | | 4:42.2 | Q, OR |
| 2 | Bill Smith | | 4:45.3 | Q |
| 3 | John Marshall | | 4:51.4 | Q |
| 4 | Géza Kádas | | 4:52.8 | Q |
| 5 | Jack Hale | | 4:53.3 | Q |
| 5 | Alex Jany | | 4:53.3 | Q |
| 7 | Per-Olof Östrand | | 4:53.5 | Q |
| 8 | Alfredo Yantorno | | 4:53.8 | Q |
| 9 | György Mitró | | 4:56.0 | Q |
| 10 | Bill Heusner | | 4:58.3 | Q |
| 11 | Don Johnston | | 4:57.4 | Q |
| 12 | Miroslav Bartůšek | | 4:57.9 | q |
| 13 | Branko Vidović | | 4:58.7 | q |
| 14 | Janko Puhar | | 5:00.8 | q |
| 15 | Marijan Stipetić | | 5:01.4 | q |
| 16 | Imre Nyéki | | 5:01.8 | Q |
| 17 | Luis González | | 5:02.1 | |
| 18 | Roy Botham | | 5:03.4 | |
| 19 | Jo Bernardo | | 5:03.8 | |
| 20 | Florbel Pérez | | 5:04.7 | |
| 21 | René Cornu | | 5:05.2 | |
| 22 | José Durañona | | 5:05.8 | |
| 23 | Garrick Agnew | | 5:06.1 | |
| 24 | Luis Child | | 5:08.5 | |
| 25 | Isidoro Martínez-Vela | | 5:10.0 | |
| 26 | Juan Garay | | 5:10.4 | |
| 27 | Doug Gibson | | 5:13.4 | |
| 28 | Isidoro Pérez | | 5:16.1 | |
| 29 | Ari Guðmundsson | | 5:16.2 | |
| 30 | Alejandro Febrero | | 5:16.9 | |
| 31 | Tom Holt | | 5:20.7 | |
| 32 | Derek Oatway | | 5:20.9 | |
| 33 | Allen Gilchrist | | 5:21.5 | |
| 34 | Sambiao Basanung | | 5:21.5 | |
| 35 | Walter Schneider | | 5:25.5 | |
| 36 | Walter Bardgett | | 5:37.2 | |
| 37 | Robert Cook | | 5:37.9 | |
| 38 | Bimal Chandra | | 5:38.6 | |
| 39 | Jack Hakim | | 5:40.3 | |
| 40 | Anwar Aziz Chaudhry | | 6:17.4 | |
| 41 | Sultan Karim Ali | | 7:16.9 | |
Key: OR = Olympic record, Q = qualification by place in heat, q = qualification by overall placeSemifinals
| Rank | Athlete | Country | Time | Notes |
| 1 | Géza Kádas | | 4:47.8 | Q |
| 2 | William Smith | | 4:48.4 | Q |
| 3 | Jimmy McLane | | 4:49.5 | Q |
| 4 | John Marshall | | 4:50.0 | Q |
| 5 | György Mitró | | 4:50.8 | q |
| 6 | Alex Jany | | 4:51.3 | q |
| 7 | Jack Hale | | 4:51.4 | q |
| 8 | Alfredo Yantorno | | 4:57.3 | q |
| 9 | Bill Heusner | | 4:57.4 | |
| 10 | Marjan Stipetić | | 4:58.6 | |
| 11 | Janko Puhar | | 4:58.7 | |
| 11 | Miroslav Bartůšek | | 4:58.7 | |
| 13 | Branko Vidović | | 4:59.4 | |
| 14 | Don Johnston | | 4:59.5 | |
Key: Q = qualification by place in heat, q = qualification by overall placeFinal
| Rank | Athlete | Country | Time | Notes |
| Bill Smith | | 4:41.0 | OR |
| Jimmy McLane | | 4:43.4 | |
| John Marshall | | 4:47.4 | |
| 4 | Géza Kádas | | 4:49.4 | |
| 5 | György Mitró | | 4:49.9 | |
| 6 | Alex Jany | | 4:51.4 | |
| 7 | Jack Hale | | 4:55.9 | |
| 8 | Alfredo Yantorno | | 4:58.7 | |
Key: OR = Olympic record
