RUNNING
Race time predictor
Project race times from a completed run using a transparent fatigue assumption and a constant-pace comparison.
Compare projected times
Your result and any downloadable splits will appear here.
How it works
Riegel-style projection = completed time × (target distance ÷ completed distance)^exponent. The default 1.06 is a commonly used assumption. A larger exponent projects more slowdown as distance increases; 1 is constant pace.
Longer distances require endurance and preparation that a short result cannot establish. Treat this as a comparison, not an expected result.
Riegel · Athletic records and human endurance ↗