In short: Running pace is time divided by distance, usually written as minutes per mile or per kilometer: a 5 km run in 25:00 is a pace of 5:00 per km (8:03 per mile).
About Running Pace Calculator
Pace is the language of running: training plans, race goals and watches all talk in minutes per kilometer or per mile. This calculator converts between distance, time and pace in either unit — enter two and it fills in the third — and shows your speed in km/h and mph.
It also predicts equivalent times for standard race distances using the Riegel endurance formula, a widely used rule of thumb published in 1977. A 25-minute 5K, for example, suggests about 52 minutes for 10K and 1:55 for a half marathon, if you have trained for the distance.
How to use Running Pace Calculator
- Choose whether to find pace, time or distance.
- Enter the other two values — pick a race to fill in its distance.
- Read the result, speed and equivalent race times.
Examples
Sub-4-hour marathon: 42.195 km in 3:59:59 → pace 5:41 /km (9:09 /mi).
Run 8 km at 6:00 /km → time 48:00.
Frequently asked questions
How do I convert pace per km to per mile?
Multiply by 1.609344. A 5:00 /km pace is 8:03 /mi.
What is a good 5K time?
It varies hugely with age and experience; many recreational runners finish between 25 and 35 minutes.
Can I type time without hours?
Yes. 25:00 is read as 25 minutes; 1:45:30 as 1 hour 45 minutes 30 seconds.
Does it work for cycling or walking?
Yes, for any steady activity; the race predictions are calibrated for running.
Updated November 2026 · Free, no signup · How we build and test tools