Running Pace Calculator

Pace is how long it takes to cover one unit of distance, written as minutes and seconds per kilometre or per mile. A 5:00 /km pace means five minutes for each kilometre. Lower numbers mean you are running faster, which is the opposite of speed, where higher is faster.

Multiply your pace per kilometre by 1.609344 to get pace per mile, since a mile is that many kilometres long. The tool shows both at once from a single calculation, so 5:00 /km appears alongside 8:03 /mi without any manual conversion.

Yes. The distance unit and the pace unit are chosen separately, and everything is reduced to seconds per kilometre internally before the answer is converted back. That lets you enter a race distance in miles while planning your pace in min/km, or any other combination.

About 5:41 /km or 9:09 /mi held for the full 42.195 km. To confirm the exact figure, choose Solve for Pace, enter 42.195 km, and set the time to 3 hours 59 minutes 59 seconds; the calculator returns the pace you must average.

Once your pace is known, the tool multiplies the seconds per kilometre by 5, 10, 21.0975 and 42.195 to fill the 5K, 10K, half marathon and marathon rows. At 5:00 /km that gives 25:00, 50:00, 1:45:29 and 3:30:59.

No. They assume you hold the calculated pace evenly for the whole distance, which is the ideal even-split race. Most runners fade somewhat, so treat the marathon and half marathon predictions as a best case rather than a guarantee.

Times are rounded to the nearest whole second, and any carry rolls up correctly, so 59.6 seconds becomes the next minute. Speeds are rounded to two decimals. Because pace is stored to the second, very long distances can differ by a second or two from a hand calculation.

A zero or negative time, distance or pace cannot be solved, so the tool simply shows a prompt to enter the two known values rather than a wrong answer. Fill in two positive numbers and the results and splits appear immediately.

Yes. Every calculation runs in your browser, and nothing you type is sent to a server or saved. You can plan your training paces without creating an account or sharing any data.