Find the row that matches the VO2max on your GPS watch. Your predicted marathon time is right next to it. Read down the table to see how many points you still need for a sub-4 or sub-3:30.
The VO2max column stays fixed. Scroll sideways for VDOT and training paces.
| VO2maxml/kg/min | Marathon26.2 mi | Half13.1 mi | 10K | 5K | VDOTrunning index | E pace/mi easy | T pace/mi threshold | I pace/mi interval |
|---|---|---|---|---|---|---|---|---|
| 33 | 5:04:38 | 2:28:49 | 1:07:16 | 32:20 | 28.2 | 12:55 | 10:49 | 9:56 |
| Sub-5 | ||||||||
| 34 | 4:57:49 | 2:25:21 | 1:05:41 | 31:34 | 29.0 | 12:38 | 10:35 | 9:43 |
| 35 | 4:51:17 | 2:22:02 | 1:04:09 | 30:51 | 29.8 | 12:22 | 10:21 | 9:30 |
| 36 | 4:45:01 | 2:18:51 | 1:02:42 | 30:09 | 30.6 | 12:06 | 10:08 | 9:18 |
| 37 | 4:39:00 | 2:15:48 | 1:01:18 | 29:29 | 31.5 | 11:52 | 9:55 | 9:06 |
| 38 | 4:33:13 | 2:12:52 | 59:58 | 28:51 | 32.3 | 11:37 | 9:43 | 8:55 |
| Sub-4:30 | ||||||||
| 39 | 4:27:40 | 2:10:04 | 58:41 | 28:14 | 33.1 | 11:24 | 9:31 | 8:44 |
| 40 | 4:22:20 | 2:07:22 | 57:27 | 27:39 | 34.0 | 11:10 | 9:20 | 8:34 |
| 41 | 4:17:11 | 2:04:46 | 56:17 | 27:06 | 34.8 | 10:58 | 9:09 | 8:24 |
| 42 | 4:12:14 | 2:02:16 | 55:09 | 26:33 | 35.7 | 10:46 | 8:59 | 8:14 |
| 43 | 4:07:27 | 1:59:51 | 54:03 | 26:02 | 36.5 | 10:34 | 8:49 | 8:05 |
| 44 | 4:02:50 | 1:57:32 | 53:00 | 25:32 | 37.4 | 10:22 | 8:39 | 7:56 |
| Sub-4 | ||||||||
| 45 | 3:58:23 | 1:55:18 | 52:00 | 25:03 | 38.2 | 10:11 | 8:30 | 7:47 |
| 46 | 3:54:05 | 1:53:08 | 51:01 | 24:35 | 39.1 | 10:01 | 8:21 | 7:39 |
| 47 | 3:49:56 | 1:51:03 | 50:05 | 24:08 | 39.9 | 9:50 | 8:12 | 7:31 |
| 48 | 3:45:55 | 1:49:02 | 49:11 | 23:42 | 40.8 | 9:41 | 8:03 | 7:23 |
| 49 | 3:42:01 | 1:47:06 | 48:18 | 23:17 | 41.7 | 9:31 | 7:55 | 7:16 |
| 50 | 3:38:15 | 1:45:13 | 47:27 | 22:53 | 42.5 | 9:22 | 7:48 | 7:09 |
| 51 | 3:34:37 | 1:43:24 | 46:38 | 22:29 | 43.4 | 9:13 | 7:40 | 7:02 |
| 52 | 3:31:05 | 1:41:38 | 45:51 | 22:07 | 44.3 | 9:04 | 7:33 | 6:55 |
| Sub-3:30 | ||||||||
| 53 | 3:27:39 | 1:39:56 | 45:05 | 21:45 | 45.2 | 8:55 | 7:25 | 6:48 |
| 54 | 3:24:20 | 1:38:17 | 44:21 | 21:23 | 46.0 | 8:47 | 7:19 | 6:42 |
| 55 | 3:21:06 | 1:36:41 | 43:38 | 21:03 | 46.9 | 8:39 | 7:12 | 6:36 |
| 56 | 3:17:58 | 1:35:08 | 42:56 | 20:43 | 47.8 | 8:32 | 7:05 | 6:30 |
| 57 | 3:14:56 | 1:33:38 | 42:16 | 20:23 | 48.7 | 8:24 | 6:59 | 6:24 |
| 58 | 3:11:59 | 1:32:10 | 41:37 | 20:04 | 49.6 | 8:17 | 6:53 | 6:18 |
| 59 | 3:09:06 | 1:30:45 | 40:59 | 19:46 | 50.5 | 8:10 | 6:47 | 6:13 |
| 60 | 3:06:19 | 1:29:23 | 40:22 | 19:28 | 51.4 | 8:03 | 6:41 | 6:08 |
| 61 | 3:03:36 | 1:28:02 | 39:46 | 19:11 | 52.3 | 7:56 | 6:36 | 6:02 |
| 62 | 3:00:57 | 1:26:44 | 39:12 | 18:54 | 53.2 | 7:49 | 6:30 | 5:57 |
| Sub-3 | ||||||||
| 63 | 2:58:23 | 1:25:29 | 38:38 | 18:38 | 54.1 | 7:43 | 6:25 | 5:53 |
| 64 | 2:55:52 | 1:24:15 | 38:05 | 18:22 | 55.0 | 7:37 | 6:20 | 5:48 |
| 65 | 2:53:26 | 1:23:03 | 37:33 | 18:06 | 55.9 | 7:31 | 6:15 | 5:43 |
| 66 | 2:51:03 | 1:21:53 | 37:02 | 17:51 | 56.8 | 7:25 | 6:10 | 5:39 |
| 67 | 2:48:44 | 1:20:46 | 36:32 | 17:37 | 57.8 | 7:19 | 6:05 | 5:34 |
| 68 | 2:46:29 | 1:19:39 | 36:02 | 17:22 | 58.7 | 7:14 | 6:00 | 5:30 |
| 69 | 2:44:17 | 1:18:35 | 35:34 | 17:08 | 59.6 | 7:08 | 5:56 | 5:26 |
| 70 | 2:42:08 | 1:17:32 | 35:06 | 16:55 | 60.5 | 7:03 | 5:51 | 5:22 |
| 71 | 2:40:02 | 1:16:31 | 34:38 | 16:42 | 61.5 | 6:58 | 5:47 | 5:18 |
| 72 | 2:37:59 | 1:15:31 | 34:12 | 16:29 | 62.4 | 6:53 | 5:43 | 5:14 |
| 73 | 2:35:59 | 1:14:33 | 33:46 | 16:16 | 63.3 | 6:48 | 5:39 | 5:10 |
| 74 | 2:34:02 | 1:13:36 | 33:21 | 16:04 | 64.3 | 6:43 | 5:35 | 5:07 |
| 75 | 2:32:08 | 1:12:41 | 32:56 | 15:52 | 65.2 | 6:38 | 5:31 | 5:03 |
| 76 | 2:30:16 | 1:11:47 | 32:32 | 15:40 | 66.2 | 6:33 | 5:27 | 4:59 |
| Sub-2:30 | ||||||||
| 77 | 2:28:27 | 1:10:54 | 32:08 | 15:28 | 67.1 | 6:29 | 5:23 | 4:56 |
| 78 | 2:26:40 | 1:10:03 | 31:45 | 15:17 | 68.1 | 6:24 | 5:19 | 4:53 |
| 79 | 2:24:55 | 1:09:12 | 31:23 | 15:06 | 69.0 | 6:20 | 5:16 | 4:49 |
| 80 | 2:23:13 | 1:08:23 | 31:01 | 14:56 | 70.0 | 6:16 | 5:12 | 4:46 |
Your watch’s VO2max and VDOT are different numbers
VO2max is, strictly speaking, a lab measurement: the maximum amount of oxygen your body can take in, measured with a mask on a treadmill. A GPS watch estimates that value from your heart rate and running speed. VDOT is different. It is a performance index worked back from an actual race time, so it also reflects how efficiently you run.
Both are expressed in ml/kg/min, which makes them easy to confuse, but for the same runner they can be 8 to 10 points apart. A watch may show 54 while the VDOT from a recent race is around 46. This table puts the watch-style (physiological) scale in the first column and VDOT in the sixth.
Use the VDOT side for training paces
E pace is easy running, T pace is threshold running you could hold for about 20 minutes, and I pace is hard running in 3 to 5 minute repeats. All three are calculated from VDOT, so a recent race time is a better starting point than the number on your watch.
Predicted times assume good conditions
Weather, hills and pacing all change the result. In races warmer than 20°C (68°F) or on hilly courses, expect to finish several minutes to well over ten minutes slower than this table. Using these times directly as your race pace is a common cause of slowing down after 30 km (about 18.6 miles).
How the numbers are calculated
Predicted times use the Daniels-Gilbert equations (Daniels and Gilbert, Oxygen Power, 1979), which account for the fact that the share of VO2max you can sustain drops as a race gets longer. The conversion to the physiological scale uses the Cooper formula, which estimates maximal oxygen uptake from the distance covered in a 12-minute all-out run (Cooper, JAMA, 1968). Training paces are the speeds that correspond to 70%, 88% and 98% of VDOT.