Running Pace Calculator
Convert between pace, speed, and finish time, and get equivalent race predictions and training paces.
Your details
Target time
This calculator runs entirely on your device. Nothing you enter is uploaded, stored, or sold. How this works
Required pace
8:01 /mi
4:59 /km · 7.49 mph · 12.06 km/h
Includes your inputs, the full breakdown, and every row of the table.
Finish time
1:45:00
13.11 mi / 21.10 km
Pace per km
4:59 /km
Speed
7.49 mph
12.06 km/h
400m split
1:59
| Race | Predicted time | Pace per mile |
|---|---|---|
| 5K | 22:50 | 7:21 /mi |
| 10K | 47:35 | 7:40 /mi |
| 10 miles | 1:18:48 | 7:53 /mi |
| Half marathon | 1:45:00 | 8:01 /mi |
| Marathon | 3:38:55 | 8:21 /mi |
What this means
- Easy training pace is roughly 10:25–11:37 per mile; tempo pace sits near 8:29.
- Riegel's formula assumes proportionate training for the distance. Marathon predictions from a 5K time are optimistic unless your endurance base supports them.
How the running pace calculation works
Pace and speed are the same information expressed two ways: pace is time per unit distance, speed is distance per unit time. Runners think in pace because it maps directly onto what a watch shows mid-run and onto splits.
Equivalent race times use Peter Riegel's formula, which raises the distance ratio to the power 1.06 to account for the fact that you cannot hold 5K pace for a marathon. It is remarkably accurate between adjacent distances and increasingly optimistic as you extrapolate further.
Frequently asked questions
What is a good marathon pace?
Recreational marathoners typically finish between 4 and 5 hours, which is roughly 9:10 to 11:30 per mile. What matters more than the absolute number is whether the pace is sustainable given your long-run training.
How do I convert min/mile to min/km?
Divide the per-mile pace by 1.609. An 8:00 mile is about 4:58 per kilometre.
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Disclaimer. This calculator is provided for general information and educational purposes only and does not constitute financial, tax, legal, medical, or engineering advice. Results are estimates based on the inputs you provide and the assumptions described above. Confirm any figure with a qualified professional before acting on it.