Pace Calculator
Choose what you want to find, then enter the other two values: distance and time to get your pace, distance and pace to get your finish time, or time and pace to get the distance. The calculator also shows your speed, a table of split times for every kilometre or mile, and predicted times for a mile, 5K, 10K, half marathon and marathon based on the effort you entered. Use kilometres or miles. Everything runs in your browser.
| Km | Split | Elapsed |
|---|---|---|
| 1 | 5:00 | 5:00 |
| 2 | 5:00 | 10:00 |
| 3 | 5:00 | 15:00 |
| 4 | 5:00 | 20:00 |
| 5 | 5:00 | 25:00 |
| 6 | 5:00 | 30:00 |
| 7 | 5:00 | 35:00 |
| 8 | 5:00 | 40:00 |
| 9 | 5:00 | 45:00 |
| 10 | 5:00 | 50:00 |
| Race | Time | Pace per km |
|---|---|---|
| 1 mile | 7:13 | 4:29 |
| 5K | 23:59 | 4:48 |
| 10K | 50:00 | 5:00 |
| Half marathon | 1:50:19 | 5:14 |
| Marathon | 3:50:01 | 5:27 |
Pace is time per kilometre or per mile, speed is distance per hour, and any two of distance, time and pace give the third. A mile is 1.609344 kilometres. The predicted race times use Pete Riegel's formula, new time = known time times (new distance / known distance) to the power 1.06. It is an estimate for trained runners with a similar build-up, and it is less reliable for very short efforts and for the marathon. The split table assumes an even pace. Everything is worked out in your browser.
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Math & MoneyAbout the Pace Calculator
Pace is the time it takes to cover one unit of distance, usually written as minutes and seconds per kilometre or per mile, and speed is the distance covered per hour. Any two of distance, time and pace give the third: pace is time divided by distance, time is distance times pace, and distance is time divided by pace. A 10 km run in 50:00 is a pace of 5:00 per kilometre, which is 8:03 per mile and a speed of 12 km/h. At that pace a marathon of 42.195 km takes about 3:31. One mile is 1.609344 kilometres, which is how the calculator converts between the two. The split table assumes you hold an even pace, and shows the time for each unit and the running total. The race predictions use Pete Riegel's formula, new time = known time x (new distance / known distance) to the power 1.06. It works best for runners with a similar training base for both distances, and it tends to be optimistic for the marathon if you have not trained for it. Treat a prediction as a starting point for planning, not a promise.
How do I calculate running pace?▾
Divide your time by your distance. A 10 km run in 50 minutes is 50 divided by 10, so 5 minutes per kilometre. To get the pace per mile, multiply the pace per kilometre by 1.609344.
How do I convert pace from km to miles?▾
Multiply the pace per kilometre by 1.609344 to get the pace per mile, and divide the pace per mile by 1.609344 to go the other way. A 5:00 per kilometre pace is about 8:03 per mile.
What pace do I need for a sub-4 hour marathon?▾
The marathon is 42.195 km, so 4 hours means 240 minutes divided by 42.195, which is about 5:41 per kilometre or 9:09 per mile, held for the whole race.
How accurate are the race predictions?▾
They use Riegel's formula, which is a reasonable estimate when you have trained for the longer distance. It is less reliable for very short efforts and for first marathons, so use it as a guide.
Is my data uploaded?▾
No. The calculation runs in your browser and nothing you enter is sent anywhere.