Race time predictor
Pete Riegel's formula predicts a race time at any target distance from a known race. Best inside the 800 m — marathon range. Assumes similar terrain and even effort.
Known race
Predictions
| Target distance | Predicted time |
|---|---|
| 1500 m | 6:08 |
| Mile | 6:37 |
| 5 km | 22:00 |
| 10 km | 45:52 |
| Half marathon | 1:41:12 |
| Marathon | 3:31:00 |
Formula: T₂ = T₁ × (D₂ / D₁)^1.06 (Pete Riegel, 1981).
Source: Peter Riegel — Race prediction formula, first published in Runner's World, 1981.