Miles & Methods

Race Time Predictor

Enter one race result and instantly see predicted finish times for every standard distance — 5K to marathon — using the research-backed Riegel formula.

CompareZonesPredict
:
:
5K
25:00
8:03/mile
10K
52:07
8:23/mile
Half
1:55:00
8:46/mile
Marathon
3:59:47
9:09/mile
50K
4:47:02
9:14/mile

T₂ = T₁ × (D₂/D₁)^1.06 — Riegel, American Scientist, 1981