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Interactive Tool · Running & Endurance

Race Time Predictor

Predict your race finish time using the Riegel formula — based on a recent race result.

Predicted Finish Time

Training Paces

Riegel Formula: T2 = T1 × (D2/D1)^1.06. Developed by Pete Riegel (1977). Accurate within ~2% for most runners.
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Race-Ready Essentials All links use our Amazon Associates tag — thank you for supporting TSP.

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