| Event: | Women's 800 metre freestyle |
| Competition: | 2021 FINA World Swimming Championships (25 m) |
| Venue: | Etihad Arena |
| Location: | Abu Dhabi, United Arab Emirates |
| Dates: | 17 December (heats) 18 December (final) |
| Competitors: | 31 |
| Nations: | 23 |
| Win Value: | 8:02.90 CR |
| Gold: | Li Bingjie |
| Goldnoc: | CHN |
| Silver: | Anastasiya Kirpichnikova |
| Bronze: | Simona Quadarella |
| Bronzenoc: | ITA |
| Prev: | 2018 |
| Next: | 2022 |
The Women's 800 metre freestyle competition of the 2021 FINA World Swimming Championships (25 m) was held on 17 and 18 December 2021.[1]
Prior to the competition, the existing world and championship records were as follows.
The following new records were set during this competition:
The heats were started on 17 December at 11:14.[2]
| Rank | Heat | Lane | Name | Nationality | Time | Notes |
|---|---|---|---|---|---|---|
| 1 | 3 | 6 | 8:10.08 | Q | ||
| 2 | 4 | 8 | 8:13.37 | Q,, NR | ||
| 3 | 4 | 5 | 8:13.61 | Q | ||
| 4 | 3 | 4 | 8:14.10 | Q | ||
| 5 | 4 | 4 | 8:14.53 | Q | ||
| 6 | 4 | 3 | 8:15.01 | Q | ||
| 7 | 4 | 6 | 8:16.01 | Q, | ||
| 8 | 3 | 3 | 8:17.03 | Q | ||
| 9 | 3 | 0 | 8:20.65 | Q | ||
| 10 | 3 | 5 | 8:21.81 | Q | ||
| 11 | 3 | 7 | 8:24.78 | |||
| 12 | 4 | 0 | 8:24.93 | |||
| 13 | 3 | 2 | 8:25.02 | |||
| 14 | 4 | 2 | 8:27.79 | |||
| 14 | 2 | 4 | 8:28.94 | |||
| 16 | 2 | 7 | 8:29.17 | |||
| 17 | 4 | 7 | 8:32.17 | |||
| 18 | 3 | 9 | 8:33.12 | |||
| 19 | 4 | 9 | 8:33.81 | |||
| 20 | 3 | 1 | 8:33.89 | |||
| 21 | 4 | 1 | 8:34.14 | |||
| 22 | 2 | 3 | 8:39.56 | |||
| 23 | 2 | 0 | 8:39.81 | NR | ||
| 24 | 2 | 5 | 8:40.55 | |||
| 25 | 2 | 2 | 8:41.94 | |||
| 26 | 2 | 8 | 8:44.10 | NR | ||
| 27 | 2 | 9 | 8:44.88 | |||
| 28 | 2 | 6 | 8:49.05 | |||
| 29 | 1 | 5 | 8:56.29 | |||
| 30 | 2 | 1 | 8:59.55 | |||
| 31 | 1 | 4 | 9:13.03 | |||
| 1 | 3 | DNS | ||||
| 1 | 6 | |||||
| 3 | 8 |
The final was held on 18 December at 19:41.[3]
| Rank | Lane | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|---|
| 4 | 8:02.90 | CR | ||||
| 6 | Russian Swimming Federation | 8:06.44 | ||||
| 3 | 8:07.99 | |||||
| 4 | 5 | 8:08.26 | ||||
| 5 | 7 | Russian Swimming Federation | 8:14.84 | |||
| 6 | 2 | 8:17.60 | ||||
| 7 | 1 | 8:20.13 | ||||
| 8 | 8 | 8:20.18 |