Marathon Race Predictor
Predict your marathon, half marathon, 10K, and 5K finish times
Your Information
mins
Calculated Output
Predicted Marathon Time
3h 40m 49s
Predicted Half Marathon
1h 45m 54s
Required Marathon Pace
5.23 min/km
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Pete Riegel Power Law Formula
T₂ = T₁ × (D₂ / D₁)^1.06 assumes proper aerobic base volume training.
- •Fatigue factor exponent (1.06) accounts for glycogen depletion over marathon distance.
Frequently Asked Questions
Is Riegel formula reliable for beginners?▼
It is very accurate if weekly mileage matches marathon distance requirements (>50-60 km/week).