Race predictor
Start from a race result and see equivalent times at other distances (Riegel and VDOT), plus approximate training paces.
Your result
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Prediction
How it works
Riegel uses T₂ = T₁ × (D₂ / D₁)^k, often with k = 1.06. VDOT describes performance from speed and time; it is not a laboratory measurement of VO₂max.
Example: 40:00 for 10K, Riegel 1.06
| Distance | Model time |
|---|---|
| 5 km | 19:11 |
| 10 km | 40:00 |
| 21.0975 km | 1:28:15 |
| 42.195 km | 3:04:00 |
Frequently asked questions
Is the prediction a promise?
No. Endurance, training background, weather and course all affect results. A short race can overestimate marathon readiness.
Which result should I use?
Use a recent, representative race with reliable distance and timing. Prefer races in comparable conditions.