keisoku

Running Pace Calculator

Enter the distance you ran and your time (hours, minutes, seconds) to instantly get your pace per kilometer (min'sec"/km) and speed (km/h). Also shows predicted times for 5K, 10K, half, and full marathon at the same pace.

Input

Distance run

km

Time taken

h
min
sec

Result

Pace per km

5'00"/km

Speed

12.00 km/h

Per km

5'00"

Distance

10.0 km

Predicted times at this pace

DistancePredicted time
1km5:00
5km25:00
10km50:00
Half marathon1:45:29
Full marathon3:30:59

How it works

  • Pace (seconds per km) is calculated as total time in seconds divided by distance in km. The result is shown in m'ss"/km format (for example, 5'00"/km), with seconds rounded to the nearest whole number.
  • Speed (km/h) is distance in km divided by the total time in hours, i.e. distanceKm / (totalSeconds / 3600).
  • Time is entered in separate hour, minute, and second fields and combined as totalSeconds = hours * 3600 + minutes * 60 + seconds. A result is shown only when the distance is greater than 0 and no more than 1000 km and the time is at least 1 second.
  • The predicted-time table keeps the same pace (seconds per km) and computes the total time for 1 km, 5 km, 10 km, a half marathon (21.0975 km), and a full marathon (42.195 km) as paceSecPerKm * distanceKm. Times of one hour or more are shown as h:mm:ss, and shorter times as m:ss.
  • These figures are calculated estimates only. Your actual race times will vary with weather, course elevation, fitness, and fatigue.