Race time predictor
Type a recent race. Both published models predict your time on every other distance.
Type a time like 1:45:00 and a pace like 8:00.
| Distance | Riegel | Daniels VDOT | Pace /mi |
|---|---|---|---|
| Mile | 7:13 | 7:07 | 7:13 |
| 5K | 23:59 | 24:06 | 7:43 |
| 10K | 50:00 | 50:00 | 8:03 |
| Half marathon | 1:50:19 | 1:50:52 | 8:25 |
| Marathon | 3:50:01 | 3:49:34 | 8:46 |
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10K equivalents (Riegel)
| 10K | 5K | Half marathon | Marathon |
|---|---|---|---|
| 35:00 | 16:47 | 1:17:13 | 2:41:00 |
| 40:00 | 19:11 | 1:28:15 | 3:04:00 |
| 45:00 | 21:35 | 1:39:17 | 3:27:01 |
| 50:00 | 23:59 | 1:50:19 | 3:50:01 |
| 55:00 | 26:23 | 2:01:21 | 4:13:01 |
| 1:00:00 | 28:47 | 2:12:23 | 4:36:01 |
| 1:05:00 | 31:11 | 2:23:25 | 4:59:01 |
| 1:10:00 | 33:34 | 2:34:27 | 5:22:01 |
Jack Daniels and Jimmy Gilbert, Oxygen Power (1979), tables in Daniels' Running Formula, 4th edition
FAQ
What marathon time does a 50-minute 10K predict?
3:50:01 with Riegel, 3:49:34 with Daniels' VDOT. Both assume marathon-specific training.
How does the Riegel formula work?
T2 = T1 × (D2 ÷ D1)^1.06: doubling the distance multiplies the time by 2.085. Peter Riegel built it on world records (1981).
Which half marathon time matches a 50-minute 10K?
1:50:19 with Riegel.