# Swimming at the 2015 World Aquatics Championships – Women's 800 metre freestyle

The Women's 800 metre freestyle competition of the swimming events at the 2015 World Aquatics Championships was held on 7 August with the heats and 8 August with the final.

## Records

Prior to the championships, the existing world and championship records were as follows.
| World record | Katie Ledecky (USA) | 8:11.00 | Shenandoah, United States | 22 June 2014 |
| Competition record | Katie Ledecky (USA) | 8:13.86 | Barcelona, Spain | 3 August 2013 |
During the competition, prior to this 800 metre event, on 4 August 2015, Katie Ledecky set a new championship record in the 1500 metre freestyle final; her 800-meter mark was at 8:13.25.
| Date | Event | Name | Nationality | Time | Record |
| 4 August | Women's 1500 m freestyle finals | Katie Ledecky | United States | 8:13.25† | CR |
| 8 August | Final | Katie Ledecky | United States | 8:07.39 | WR, CR |
Legend: † – en route to final mark

## Results
### Heats

The heats were held at 11:17
| Rank | Heat | Lane | Name | Nationality | Time | Notes |
| 1 | 5 | 4 | Katie Ledecky | United States | 8:19.42 | Q |
| 2 | 4 | 5 | Jessica Ashwood | Australia | 8:22.17 | Q |
| 3 | 5 | 6 | Lotte Friis | Denmark | 8:23.12 | Q |
| 4 | 5 | 5 | Lauren Boyle | New Zealand | 8:23.66 | Q |
| 5 | 4 | 4 | Jazmin Carlin | Great Britain | 8:23.83 | Q |
| 6 | 4 | 6 | Sharon van Rouwendaal | Netherlands | 8:24.83 | Q, NR |
| 7 | 4 | 2 | Sarah Köhler | Germany | 8:26.16 | Q |
| 8 | 5 | 3 | Boglárka Kapás | Hungary | 8:26.96 | Q |
| 9 | 5 | 2 | Leonie Beck | Germany | 8:28.39 | |
| 10 | 4 | 3 | Becca Mann | United States | 8:28.44 | |
| 11 | 3 | 2 | Kristel Köbrich | Chile | 8:33.12 | |
| 12 | 5 | 8 | Andreina Pinto | Venezuela | 8:33.33 | |
| 13 | 4 | 7 | Melani Costa | Spain | 8:34.89 | |
| 14 | 5 | 9 | Zhang Yuhan | China | 8:35.17 | |
| 15 | 4 | 1 | Jessica Thielmann | Great Britain | 8:36.88 | |
| 16 | 5 | 7 | Martina Caramignoli | Italy | 8:38.56 | |
| 17 | 4 | 8 | Tjasa Oder | Slovenia | 8:38.85 | |
| 18 | 3 | 7 | Julia Hassler | Liechtenstein | 8:39.12 | |
| 19 | 5 | 1 | Erica Musso | Italy | 8:39.55 | |
| 20 | 2 | 5 | Valerie Gruest | Guatemala | 8:39.88 | |
| 21 | 3 | 3 | Samantha Arévalo | Ecuador | 8:41.15 | |
| 22 | 4 | 0 | Beatriz Gómez Cortés | Spain | 8:41.72 | |
| 23 | 2 | 3 | María Álvarez | Colombia | 8:42.14 | NR |
| 24 | 3 | 0 | Montserrat Ortuño | Mexico | 8:42.83 | |
| 25 | 3 | 4 | Cao Yue | China | 8:43.24 | |
| 26 | 3 | 5 | Leah Neale | Australia | 8:44.38 | |
| 27 | 4 | 9 | Emma Robinson | New Zealand | 8:44.86 | |
| 28 | 3 | 9 | Monique Olivier | Luxembourg | 8:45.37 | |
| 29 | 3 | 6 | Joanna Evans | Bahamas | 8:49.96 | |
| 30 | 2 | 4 | Martina Elhenická | Czech Republic | 8:53.08 | |
| 31 | 2 | 6 | Khoo Cai Lin | Malaysia | 8:55.20 | |
| 32 | 3 | 1 | Jo Hyun-ju | South Korea | 8:57.66 | |
| 33 | 2 | 1 | Daniela Miyahara | Peru | 9:00.30 | |
| 34 | 2 | 2 | Rachel Tseng | Singapore | 9:01.19 | |
| 35 | 2 | 7 | Daniella van den Berg | Aruba | 9:03.71 | |
| 36 | 2 | 9 | Helena Moreno | Costa Rica | 9:09.27 | |
| 37 | 3 | 8 | Valeriya Salamatina | Russia | 9:11.78 | |
| 38 | 2 | 8 | Hannah Gill | Barbados | 9:16.23 | |
| 39 | 2 | 0 | Talita Te Flan | Ivory Coast | 9:16.89 | |
| 40 | 1 | 4 | Gabriella Doueihy | Lebanon | 9:18.30 | |
| 41 | 1 | 5 | Lena Rannvaardottir | Faroe Islands | 9:35.53 | |
| 42 | 1 | 3 | Makaela Holowchak | Antigua and Barbuda | 9:37.68 | |
| 43 | 1 | 6 | Victoria Chentsova | Northern Mariana Islands | 9:48.87 | |
| | 5 | 0 | Coralie Balmy | France | | DNS |

### Final

The final was held on 8 August at 18:55.
| Rank | Lane | Name | Nationality | Time | Notes |
| | 4 | Katie Ledecky | United States | 8:07.39 | WR |
| | 6 | Lauren Boyle | New Zealand | 8:17.65 | OC |
| | 2 | Jazmin Carlin | Great Britain | 8:18.15 | |
| 4 | 5 | Jessica Ashwood | Australia | 8:18.41 | NR |
| 5 | 3 | Lotte Friis | Denmark | 8:21.36 | |
| 6 | 8 | Boglárka Kapás | Hungary | 8:22.93 | |
| 7 | 1 | Sarah Köhler | Germany | 8:23.67 | |
| 8 | 7 | Sharon van Rouwendaal | Netherlands | 8:24.12 | NR |