Pace Calculator
Calculate your running pace per kilometer and per mile, plus speed in km/h and mph, from a distance and elapsed time.
How It's Calculated
Formula
\text{pace (s/km)} = \frac{\text{elapsed time (s)}}{\text{distance (km)}}
\text{speed (km/h)} = \frac{\text{distance (km)}}{\text{elapsed time (h)}}This calculator converts a distance and elapsed time into running pace (minutes per kilometer and minutes per mile) and speed (km/h and mph). Pace is simply elapsed time divided by distance; speed is distance divided by elapsed time — the two are reciprocals of each other, just expressed in different units. Distance-unit conversion (km <-> mile) uses the same exact 1609.344 m/mile constant as this site's Length Converter, so pace-per-km and pace-per-mile always describe the exact same run. This is an estimate for general informational and educational purposes, based on a published formula — it is not a medical diagnosis, and it is not a substitute for individualized advice from a qualified healthcare provider. This is pure performance math — it does not account for terrain, elevation, weather, or pacing strategy across the distance.
Worked Examples
5 km in 25 minutes
- Elapsed time: 25 min = 1,500 s
- Pace per km: 1,500 s / 5 km = 300 s/km = 5:00 / km
- Pace per mile: 300 s/km × 1.609344 km/mile ≈ 482.8 s/mile ≈ 8:03 / mile
- Speed: 5 km / (25/60 h) = 12 km/h
10 km in 60 minutes
- Elapsed time: 60 min = 3,600 s
- Pace per km: 3,600 s / 10 km = 360 s/km = 6:00 / km
- Speed: 10 km / 1 h = 10 km/h
Frequently Asked Questions
How is pace different from speed?
Pace is time per unit distance (e.g. minutes per km) — lower is faster. Speed is distance per unit time (e.g. km/h) — higher is faster. They're mathematically reciprocal descriptions of the same run.
Why do pace-per-km and pace-per-mile look different for the same run?
A mile (1.609344 km) is longer than a kilometer, so covering it takes proportionally longer — pace-per-mile is always pace-per-km multiplied by 1.609344, not a different run.
Can I enter fractional minutes and seconds?
Yes. Enter elapsed time as decimal minutes — for example, 27 minutes 30 seconds is 27.5.