Pace Calculator

Divide your mile pace by 1.609 to get your kilometre pace, or multiply your kilometre pace by 1.609 to get your mile pace. For example, 8:00 per mile is 4:58 per km, and 5:00 per km is 8:03 per mile. Enter either pace in the calculator and it converts both ways, along with your speed in mph and km/h.

You need to average 9:09 per mile, or 5:41 per km. That is also the pace for a sub-2 hour half marathon, because the half is exactly half the distance. Allow a few seconds per mile in hand, as GPS watches often measure a race slightly long and you rarely run the perfect racing line.

Both need 5:00 per km, which is 8:03 per mile. A sub-20 minute 5K and a sub-40 minute 10K both need 4:00 per km, or 6:26 per mile.

The Predicted Race Times section uses the Riegel formula, T2 = T1 x (D2 / D1)^1.06, which assumes your pace slows slightly as the distance gets longer. It works best between similar distances and assumes you have trained for the longer race, so a marathon prediction from a 5K time is often optimistic. For a more detailed prediction, try the Race Time Predictor.

Divide 60 by your speed to get minutes per unit. 10 km/h is 6:00 per km, 12 km/h is 5:00 per km and 10 mph is 6:00 per mile. Use the Treadmill Converter tab to convert any speed in km/h or mph.

The Pace Chart lists each pace per km and per mile alongside the speed in km/h and mph, and the finish time that pace gives over a 5K, 10K, half marathon and marathon. You can change the sort order, show every 0.1 km/h step or add elite speeds.