Pace, Speed & Time Converter

Convert between min/km, min/mile, km/h, and mph running paces. Predict race times and view detailed mile/kilometer split charts.

Pace Training Presets
4-Way Bidirectional Pace Sync
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Race Predictions & Target Splits
EventTarget Split Time
1,500m (1.50 km)7m 19s
5K Run (5.00 km)25m 00s
10K Run (10.00 km)50m 00s
Half Marathon (21.10 km)1h 50m 19s
Full Marathon (42.20 km)3h 50m 01s
Riegel Endurance Correction

Calculations utilize Pete Riegel's endurance prediction exponent (1.06). As distance increases, a runner's threshold speed drops naturally over extended durations due to systemic glycogen depletion and cardiovascular drift.

Explore Additional Utilities

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