| Event: | Men's 400 metre freestyle |
| Games: | 1912 Summer |
| Venue: | Djurgårdsbrunnsviken |
| Dates: | July 11–14 |
| Competitors: | 26 |
| Nations: | 13 |
| Gold: | George Hodgson |
| Goldnoc: | CAN |
| Silver: | John Hatfield |
| Silvernoc: | GBR |
| Bronze: | Harold Hardwick |
| Bronzenoc: | ANZ |
| Prev: | 1908 |
| Next: | 1920 |
The men's 400 metre freestyle was a swimming event held as part of the swimming at the 1912 Summer Olympics programme.[1] It was the third appearance of the event, which had been introduced in 1904. The competition was held from Thursday July 11, 1912 to Sunday July 14, 1912.
Twenty-six swimmers from 13 nations competed.
These were the standing world and Olympic records (in minutes) prior to the 1912 Summer Olympics.
| World Record | 5:28.4 |  Béla Las-Torres | Budapest (HUN) | June 5, 1912 | |
|---|---|---|---|---|---|
| Olympic Record | 5:36.8 |  Henry Taylor | London (GBR) | July 16, 1908 |
In the first heat Harold Hardwick set a new Olympic record with 5:36.0 minutes. In the fifth heat Cecil Healy improved the Olympic record with 5:34.0 minutes. In the first semi-final George Hodgson set a world record with 5:25.4 minutes and in the final he improved his record again with 5:24.4 minutes.
The top two in each heat advanced along with the fastest loser overall.
Heat 1
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 5:36.0 | QS OR | ||||
| 2 | 5:37.0 | QS | ||||
| 3 | 6:10.2 | |||||
| 4 | 6:23.4 | |||||
| 5 | ||||||
| — | DNF |
Heat 2
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 6:03.6 | QS | ||||
| 2 | 6:14.4 | QS | ||||
| 3 | 6:29.8 | |||||
| — | DNF |
Heat 3
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 5:44.6 | QS | ||||
| 2 | 5:46.0 | QS | ||||
| 3 | 5:50.4 | qs | ||||
| — | DNF | |||||
| DNF |
Heat 4
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 5:36.2 | QS | ||||
| 2 | 5:48.4 | QS | ||||
| — | DNF |
Heat 5
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 5:34.0 | QS OR | ||||
| 2 | 5:35.6 | QS | ||||
| 3 | 6:09.4 |
Heat 6
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 5:50.6 | QS | ||||
| 2 | 5:52.4 | QS | ||||
| 3 | 5:57.0 | |||||
| 4 | 6:30.6 | |||||
| 5 | 7:07.8 |
The top two from each heat and the faster of the two third place swimmers advanced.
Semifinal 1
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 5:25.4 | QF WR | ||||
| 2 | 5:25.6 | QF | ||||
| 3 | 5:49.0 | |||||
| 4 | 5:51.0 | |||||
| 5 | 5:51.2 | |||||
| 6 | ||||||
| — | DNS |
Semifinal 2
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 5:31.0 | QF | ||||
| 2 | 5:34.8 | QF | ||||
| 3 | 5:37.8 | qf | ||||
| 4 | 5:38.0 | |||||
| 5 | 5:48.2 | |||||
| — | DNS |
| Place | width=200 | Swimmer | width=90 | Time |
|---|---|---|---|---|
| 1 | 5:24.4 WR | |||
| 2 | 5:25.8 | |||
| 3 | 5:31.2 | |||
| 4 | 5:37.8 | |||
| 5 | 5:42.0 |