Sebastian Vettel led team mate Mark Webber in a Red Bull one-two in Friday afternoon’s second practice session for the 2013 Formula 1 United States Grand Prix.
The world champion set a best time of 1m 37.305 on the medium compound tyre to finish 0.115s ahead of Webber. The Mercedes duo of Nico Rosberg and Lewis Hamilton were third and fourth fastest.
| Pos. | Drivers | Teams | Time | Laps |
| 01. |  Sebastian Vettel |
Red Bull Racing | 1:37.305 | 35 |
| 02. |  Mark Webber |
Red Bull Racing | 1:37.420 | 37 |
| 03. | Nico Rosberg |
Mercedes AMG Petronas | 1:37.785 | 38 |
| 04. |  Lewis Hamilton |
Mercedes AMG Petronas | 1:37.958 | 38 |
| 05. |  Heikki Kovalainen |
Lotus F1 | 1:38.073 | 41 |
| 06. |  Esteban Gutiérrez |
Sauber F1 | 1:38.229 | 40 |
| 07. | Nico Hulkenberg |
Sauber F1 | 1:38.254 | 40 |
| 08. |  Romain Grosjean |
Lotus F1 | 1:38.255 | 33 |
| 09. | Jenson Button |
Vodafone McLaren Mercedes | 1:38.269 | 34 |
| 10. |  Fernando Alonso |
Scuderia Ferrari | 1:38.461 | 33 |
| 11. | Adrian Sutil |
Sahara Force India | 1:38.719 | 31 |
| 12. |  Felipe Massa |
Scuderia Ferrari | 1:38.938 | 37 |
| 13. | Sergio Perez |
Vodafone McLaren Mercedes | 1:38.941 | 31 |
| 14. | Daniel Ricciardo |
Scuderia Toro Rosso | 1:39.246 | 28 |
| 15. | Paul di Resta |
Sahara Force India | 1:39.410 | 34 |
| 16. | Valtteri Bottas |
Williams F1 | 1:39.512 | 37 |
| 17. | Jean-Eric Vergne |
Scuderia Toro Rosso | 1:39.579 | 36 |
| 18. |  Pastor Maldonado |
Williams F1 | 1:43.565 | 33 |
| 19. | Charles Pic |
Caterham F1 Team | 1:40.376 | 39 |
| 20. |  Giedo van der Garde |
Caterham F1 Team | 1:40.563 | 35 |
| 21. | Max Chilton |
Marussia F1 | 1:46.226 | 31 |
| 22. | Jules Bianchi |
Marussia F1 | 1:46.226 | 20 |
