The Running Pace Calculator turns a distance and a time into your pace per kilometre and per mile, your average speed, and projected finish times for the standard race distances. Whether you’re checking a training run or planning race-day strategy, it gives instant answers in your browser.
How pace is calculated
Pace is total time divided by distance:
pace = time ÷ distance
The tool converts your distance into both kilometres and miles, so you get pace per km and per mile, plus average speed in km/h and mph.
Race-time projections
From your current pace it projects finish times for 5K, 10K, half marathon (21.0975 km) and full marathon (42.195 km), assuming you hold that pace throughout.
| Distance | Based on |
|---|---|
| 5K | your pace × 5 km |
| 10K | your pace × 10 km |
| Half marathon | your pace × 21.0975 km |
| Marathon | your pace × 42.195 km |
Most runners slow over longer distances, so treat a marathon projected from a 5K pace as an optimistic ceiling, not a guarantee. Everything is calculated locally in your browser.