Running Pace & Race Time Calculator
Solve running pace, finish time or distance, convert min/km and min/mile, and generate an even split table.
Calculate pace, time or distance
Enter exactly two values. Leave the value you want to solve blank.
Splits
| Distance | Elapsed time |
|---|
This projection assumes suitable endurance preparation and comparable conditions. It is not a guaranteed result.
Exact arithmetic and estimated performance are separated
Distance, time and pace use a deterministic relationship. ToolBullet calculates internally in kilometres and seconds before converting the display. The optional equivalent-race result uses the Riegel power-law form and is clearly labelled as an estimate.
Read the formulas, split examples and projection limits.
Model reviewed 7 July 2026: peer-reviewed discussion of power-law endurance models.
Running Pace FAQ
Is min/km the same as km/h?
No. Min/km is time required per kilometre, while km/h is distance covered per hour. They describe the same average speed in inverse forms.
How do I calculate finish time from pace?
Convert the pace to seconds per kilometre or mile, multiply by the exact distance, then convert the total seconds back to hours, minutes and seconds.
Does the split table assume an even pace?
Yes. It provides evenly spaced checkpoints as a baseline. Real pacing can vary because of elevation, wind, congestion, aid stations and race tactics.
Why can an equivalent-race prediction be wrong?
The Riegel projection cannot know endurance preparation, terrain, weather, fuelling, pacing or fatigue. It is a mathematical estimate rather than a guaranteed finish time.
Why is a marathon entered as 42.195 km?
That is the standard marathon distance. Using an aggressively rounded distance produces a finish-time error that becomes more visible at slower paces.