| Final 19:45 | time | +time | L |   |  | 1. Katie Ledecky |  USA | 8:14.63 | AM | 03 |  Stats |  | 2. Mireia Belmonte Garcia |  ESP | 8:18.76 | +4.13s | 06 |  Stats |  | 3. Rebecca Adlington |  GBR | 8:20.32 | +5.69s | 04 |  Stats |  | 4. Lauren Boyle |  NZL | 8:22.72 | +8.09s | 02 |  Stats |  | 5. Lotte Friis |  DEN | 8:23.86 | +9.23s | 05 |  Stats |  | 6. Boglarka Kapas |  HUN | 8:23.89 | +9.26s | 07 |  Stats |  | 7. Coralie Balmy |  FRA | 8:29.26 | +14.63s | 08 |  Stats |  | 8. Andreina Pinto Perez |  VEN | 8:29.28 | +14.65s | 01 |  Stats |   
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   |  | Katie Ledecky |   
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| Heat 5 | time | +time | L | Rk. |   |  | 1. Rebecca Adlington |  GBR | 8:21.78 | - | 04 | 1. |  Times |  | 2. Lauren Boyle |  NZL | 8:25.91 | 4.13s | 06 | 5. |  Times |  | 3. Yiwen Shao |  CHN | 8:27.78 | 6.00s | 03 | 9. |  Times |  | 4. Erika Villaecija Garcia |  ESP | 8:27.99 | 6.21s | 02 | 10. |  Times |  | 5. Savannah King |  CAN | 8:29.72 | 7.94s | 01 | 15. |  Times |  | 6. Cecilia Biagioli |  ARG | 8:33.97 | 12.19s | 08 | 16. |  Times |  | 7. Jess Ashwood |  AUS | 8:37.21 | 15.43s | 07 | 20. |  Times |  | 8. Kate Ziegler |  USA | 8:37.38 | 15.60s | 05 | 21. |  Times |   
| Heat 4 | time | +time | L | Rk. |   |  | 1. Lotte Friis |  DEN | 8:21.89 | - | 04 | 2. |  Times |  | 2. Boglarka Kapas |  HUN | 8:26.43 | 4.54s | 03 | 6. |  Times |  | 2. Andreina Pinto Perez |  VEN | 8:26.43 | 4.54s | 08 | 6. |  Times |  | 4. Coralie Balmy |  FRA | 8:27.15 | 5.26s | -- | 8. |  Times |  | 5. Kristel Kobrich |  CHI | 8:29.55 | 7.66s | 07 | 14. |  Times |  | 6. Kylie Palmer |  AUS | 8:35.75 | 13.86s | 06 | 18. |  Times |  | 7. Camelia Potec |  ROU | 8:38.44 | 16.55s | 01 | 23. |  Times |  | 8. Xin Xin |  CHN | 8:40.88 | 18.99s | 05 | 24. |  Times |   
| Heat 3 | time | +time | L | Rk. |   |  | 1. Katie Ledecky |  USA | 8:23.84 | - | 04 | 3. |  Times |  | 2. Mireia Belmonte Garcia |  ESP | 8:25.26 | 1.42s | 05 | 4. |  Times |  | 3. Alexa Komarnycky |  CAN | 8:28.11 | 4.27s | 01 | 11. |  Times |  | 4. Wendy Trott |  RSA | 8:28.98 | 5.14s | 03 | 12. |  Times |  | 5. Eva Risztov |  HUN | 8:29.06 | 5.22s | 02 | 13. |  Times |  | 6. Ellie Faulkner |  GBR | 8:38.00 | 14.16s | 06 | 22. |  Times |  | 7. Elena Sokolova |  RUS | 8:42.73 | 18.89s | 08 | 26. |  Times |  | -. Grainne Murphy |  IRL | DNS | - | 07 |   |   |   
| Heat 2 | time | +time | L | Rk. |   |  | 1. Julia Hassler |  LIE | 8:35.18 | - | 04 | 17. |  Times |  | 2. Katya Bachrouche |  LIB | 8:35.88 | 0.70s | 02 | 19. |  Times |  | 3. Tjasa Oder |  SLO | 8:41.82 | 6.64s | 05 | 25. |  Times |  | 4. Patricia Castaneda Miyamoto |  MEX | 8:44.44 | 9.26s | 06 | 27. |  Times |  | 5. Nina Dittrich |  AUT | 8:45.41 | 10.23s | 03 | 28. |  Times |  | 6. Cai Lin Khoo |  MAS | 8:51.18 | 16.00s | 07 | 30. |  Times |  | 7. Lynette Lim |  SIN | 8:52.92 | 17.74s | 01 | 31. |  Times |  | 8. Nakyeong Han |  KOR | 8:57.26 | 22.08s | 08 | 32. |  Times |   
| Heat 1 | time | +time | L | Rk. |   |  | 1. Samantha Arevalo Salinas |  ECU | 8:49.21 | - | 04 | 29. |  Times |  | 2. Pamela Benitez |  ESA | 9:02.66 | 13.45s | 05 | 33. |  Times |  | 3. Daniella van den Berg |  ARU | 9:23.21 | 34.00s | 06 | 34. |  Times |  | 4. Simona Marinova |  KDU | 9:28.41 | 39.20s | 03 | 35. |  Times |   
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|   | F |  | Heat 5 | 2 |  | Heat 4 | 4 |  | Heat 3 | 2 |  | Heat 2  |  | Heat 1  |   
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|  Olympic Qualifying Time - 8:33.84 - 14+9 |  | Kylie Palmer | AUS | 18. | Jessica Ashwood | AUS | 20. |  | Savannah King | CAN | 15. | Alexa Komornarnycky | CAN | 11. |  | Shao Yiwen | CHN | 9. | Xin Xin | CHN | 24. |  | Rebecca Adlington | GBR | 3. | Eleanor Faulkner | GBR | 22. |  | Boglárka Kapás | HUN | 6. | Éva Risztov | HUN | 13. |  | Mireia Belmonte García | ESP | 2. | Erika Villaécija García | ESP | 10. |  | Kathleen Ledecky | USA | 1. | Kate Ziegler | USA | 21. |  | Cecilia Biagioli | ARG | 16. |  | Kristel Kobrich | CHI | 14. |  | Lotte Friis | DEN | 5. |  | Coralie Balmy | FRA | 7. |  | Gráinne Murphy | IRL | DNS |  | Lauren Boyle | NZL | 4. |  | Camelia Potec | ROU | 23. |  | Wendy Trott | RSA | 12. |  | Andreína Pinto | VEN | 8. |   
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|  Olympic Selection Time - 8:51.82 - 11 |  | Yelena Sokolova | RUS | 8:36.44 | 26. |  | Julia Hassler | LIE | 8:38.18 | 17. |  | Tjasa Oder | SLO | 8:38.24 | 25. |  | Nina Dittrich | AUT | 8:39.67 | 28. |  | Patricia Castañeda | MEX | 8:40.67 | 27. |  | Katya Bachrouche | LIB |   | 19.  |  | Sara El Bekri | MAR | qoe | - |  | Khoo Cai Lin | MAS | 8:49.28 | 30. |  | Lynette Lim | SIN | 8:50.00 | 31. |  | Han Na-Kyeong | KOR | 8:50.16 | 32. |  | Samantha Arevalo Salinas | ECU | up | 29. |  | Natthanan Junkrajang | THA | 8:51.59 | - |   
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|  Wildcard Places - 3 |  | Daniella van den Berg | ARU | 34. |  | Alexia Benitez Quijada | ESA | 33. |  | Simona Marinova | MKD | 35. |   
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| Olympic Qualification time | time | place | date | birth |  | 1. Rebecca Adlington | GBR | 8:17.51 | Shanghai(CHN) | 24.07.2011 | 17/02/1989 |  | 2. Lotte Friis | DEN | 8:18.20 | Shanghai(CHN) | 24.07.2011 | 09/02/1988 |  | 3. Kathleen Ledecky | USA | 8:19.78 | Omaha(USA) | 25.06.2012 | 17/03/1997 |  | 4. Kate Ziegler | USA | 8:21.87 | Omaha(USA) | 25.06.2012 | 27/06/1988 |  | 5. Xin Xin | CHN | 8:22.76 | Shaoxing(CHN) | 01.04.2012 | 06/11/1996 |  | 6. Mireia Belmonte Garcia | ESP | 8:22.78 | Eindhoven(NED) | 02.12.2011 | 10/11/1990 |  | 7. Yiwen Shao | CHN | 8:24.78 | Rizhao(CHN) | 21.09.2011 | 10/03/1995 |  | 8. Boglarka Kapas | HUN | 8:24.79 | Shanghai(CHN) | 24.07.2011 | 22/04/1993 |  | 9. Wendy Trott | RSA | 8:25.71 | Rome(ITA) | 14.06.2012 | 14/02/1990 |  | 10.Lauren Boyle | NZL | 8:26.30 | Shenzhen(CHN) | 14.08.2011 | 14/12/1987 |  | 11.Kylie Palmer | AUS | 8:26.60 | Adelaide(AUS) | 15.03.2012 | 25/02/1990 |  | 12.Eleanor Faulkner | GBR | 8:27.11 | London(GBR) | 03.03.2012 | 05/01/1993 |  | 13.Erika Villaecija Garcia | ESP | 8:27.76 | Malaga(ESP) | 29.03.2012 | 02/06/1984 |  | 14.Coralie Balmy | FRA | 8:27.79 | Debrecen(HUN) | 21.05.2012 | 02/06/1987 |  | 15.Eva Risztov | HUN | 8:27.87 | Debrecen(HUN) | 21.05.2012 | 30/08/1985 |  | 16.Jessica Ashwood | AUS | 8:27.97 | Adelaide(AUS) | 15.03.2012 | 28/04/1993 |  | 17.Kristel Kobrich | CHI | 8:28.76 | Shanghai(CHN) | 24.07.2011 | 09/08/1985 |  | 18.Grainne Murphy | IRL | 8:29.55 | Bronshoj(DEN) | 22.03.2012 | 26/03/1993 |  | 19.Savannah King | CAN | 8:30.79 | Montreal(CAN) | 27.03.2012 | 04/06/1992 |  | 20.Camelia Potec | ROU | 8:31.06 | Dunkerke(FRA) | 18.03.2012 | 19/02/1982 |  | 21.Alexa Komarnycky | CAN | 8:32.68 | Santa Clara(USA) | 31.05.2012 | 05/10/1989 |  | 22.Cecilia Biagioli | ARG | 8:33.17 | Rio de Janeiro(BRA) | 24.04.2012 | 03/01/1985 |  | 23.Andreina Pinto | VEN | 8:33.28 | Santa Clara(USA) | 31.05.2012 | 10/09/1991 |   
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