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Race Time Predictor (Riegel)

Predict your 5K / 10K / half / marathon time from any other race result.

Result

1 mile

7:31

10K

52:07

Half marathon

1:55:00

Marathon

3:59:47

About this tool

Enter a recent race distance and finish time to predict the equivalent finish at 1 mile, 5K, 10K, half, and full marathon using Riegel's formula (with a fatigue-factor override). The r/running 'I just ran a 25-min 5K, what can I run a half in' classic.

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