Race Time Predictor
Predict your 10K, Half Marathon and Marathon finish times based on your current performance.
0 h · 25 min · 30 sec
How does the prediction work?
We use the Riegel formula (T₂ = T₁ × (D₂/D₁)^1.06), a well-established model for endurance performance. It assumes consistent pacing ability across distances.
When does it work best?
Best for runners with consistent training and a recent race effort at maximum sustainable effort. Works well when predicting longer distances from shorter races.
What affects prediction accuracy?
Endurance base, weekly mileage, elevation, weather, nutrition and racing experience all influence how close predictions match reality.
When should you use this predictor?
Use it to set realistic race goals, plan training blocks and estimate marathon pace from a recent 5K or 10K result.
Reference race time equivalencies
| 5K time | 10K | Half | Marathon |
|---|---|---|---|
| 20:00 | 41:30 | 1:31 | 3:11 |
| 22:00 | 45:40 | 1:40 | 3:31 |
| 25:00 | 52:00 | 1:55 | 3:59 |
| 27:30 | 57:20 | 2:07 | 4:23 |
| 30:00 | 1:02 | 2:20 | 4:47 |
Ready to achieve these times?
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