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Running pace calculator and race time predictor
Enter a distance and a time to see your pace per kilometre and per mile, your average speed, and predicted finish times for other race distances.
Your pace
| Race | Predicted time | Pace /km |
|---|
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See Strava personal bestsHow the pace calculator works
Your pace is the time it takes you to cover one kilometre or one mile: your time divided by the distance. Your speed is the reverse, the distance you cover in an hour.
Race time predictions
Predicted times use Riegel's formula, a long-standing way to estimate a race time from a recent result over another distance:
Predicted time = known time × (new distance ÷ known distance)1.06
The exponent of 1.06 accounts for slowing down as races get longer. Predictions are most reliable for distances within a few times of your known result, and assume you have trained for the longer race. A 5K time is a good guide to your 10K, but predicting a marathon from a 5K is optimistic unless your endurance training is in place.
Common paces
| Pace per km | 5K | 10K | Half marathon |
|---|---|---|---|
| 4:30 | 22:30 | 45:00 | 1:34:56 |
| 5:00 | 25:00 | 50:00 | 1:45:29 |
| 5:30 | 27:30 | 55:00 | 1:56:02 |
| 6:00 | 30:00 | 1:00:00 | 2:06:35 |
Frequently asked questions
How do I calculate my running pace?
Divide your time by your distance. For example, 25 minutes for 5 km is a pace of 5:00 per kilometre.
What is a good 5K time?
It depends on age and experience. Many new runners finish a 5K in 30 to 40 minutes, while regular club runners often run under 25 minutes.
How accurate are race time predictions?
Riegel's formula is a good guide between nearby distances, such as 5K to 10K. Over much longer races it assumes you have done the training for that distance, so treat a marathon prediction from a 5K as a best case.
What is the difference between pace and speed?
Pace is the time per distance (minutes per km or mile), which runners usually use. Speed is distance per time (km/h), which is more common for cycling.
How do I convert pace per km to pace per mile?
Multiply your pace per km by 1.609. For example, 5:00 per km is about 8:03 per mile. The calculator shows both.
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