House of Calculator

Find your finish time from your pace, or your pace from a target time, for a mile, 5K, 10K, half marathon, marathon or a distance of your own.

Results are estimates for planning. Check the figures before you make a financial or health decision.

How the Running pace and finish time works

Pace is time divided by distance. Choose what you want to find, then pick a race distance: 1 mile, 5K, 10K, 10 miles, half marathon (21.0975 km), marathon (42.195 km) or your own distance in kilometres.

  • Finish time from pace: enter your pace per kilometre or per mile as minutes and seconds (for example 5:30). The tool converts to a pace per kilometre and multiplies by the distance.
  • Pace from finish time: enter a time as h:mm:ss or m:ss and the tool divides it by the distance.

The results show pace per kilometre and per mile, speed in km/h and mph, and what that same pace would give over 5K, 10K, half marathon and marathon.

Those other-distance times assume you hold exactly the same pace throughout. Most runners slow down over longer distances, so treat them as an upper limit on speed, not a prediction. The tool also flags paces that look implausibly fast or slow, which usually means the distance or time was typed wrongly.

Worked example

Using the default values in the calculator above:

InputValue
What you want to findFinish time from my pace
Race distance5K
Pace measured perKilometre
Pace5:30

Finish time: 27:30

Pace per kilometre5:30
Pace per mile8:51
Speed10.9 km/h, 6.8 mph
5K at this pace27:30
10K at this pace55:00
Half marathon at this pace1:56:02

Tips and common mistakes

Check the unit before you trust the result. Mixing up pace per mile and pace per kilometre is the most common error, and a mile pace looks about 60% slower on paper.

For a race goal, use a recent time from a similar distance and expect to be slower over a longer one. The Riegel formula, T2 = T1 × (D2/D1)^1.06, is a common way to adjust for that. Plan splits by running the first few kilometres slightly under target pace rather than over it. For a full guide, see Running pace and race finish times explained.

Frequently asked questions

How do I calculate my running pace?

Divide your total time by the distance. A 25-minute 5K is 25 ÷ 5 = 5 minutes per kilometre. The tool also gives the pace per mile.

Can I use this for a distance that is not listed?

Yes. Choose Other distance and enter it in kilometres. Distances between about 0.1 km and 1,000 km are accepted.

Will I really run a marathon at my 5K pace?

Almost certainly not. The tool holds your pace constant for comparison, but fatigue means most runners slow down noticeably over longer distances.

Guides that help

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