Fitness
Pace Calculator
Enter any two of distance, time, and pace to solve for the third, then see the equivalent finish times at common race distances.
Calculation inputs
Enter times as hh:mm:ss and pace as mm:ss per mile or kilometre.
Results
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Complete the fields and select Calculate to show results here.
About this calculator
A pace calculator solves for running or walking pace, total time, or distance once you know the other two values. Runners, coaches, and race organizers use it to plan workouts, set splits, and predict finish times.
How the calculation works
- Pace = total time ÷ distance
- Time = pace × distance
- Distance = total time ÷ pace
- Race predictions hold the same pace across every distance
Notes and assumptions
Holding one pace across every distance is optimistic for longer races — most runners slow slightly as distance grows.
How it works in plain English
Pace, time, and distance are locked together by one simple relationship: pace equals time divided by distance. Because of that, knowing any two of the three lets you solve for the missing one with basic division or multiplication. Most versions of this tool let you pick which value you want solved for, then enter the other two in whatever units you're comfortable with, typically minutes per mile or minutes per kilometer.
Once your pace is known, the calculator can also project it across other common race distances, such as a 5K, 10K, half marathon, or marathon, by multiplying that per-mile or per-kilometer pace by each distance. This is useful for comparing effort across different race lengths or for setting a target split during training.
Because pace is a rate, small rounding differences in seconds can shift longer projected times by a noticeable amount, so results are best treated as close estimates rather than exact predictions, especially over marathon distances.
The formula
- Pace = time / distance
- Time = pace x distance
- Distance = time / pace
Worked example
Suppose a runner covers 3.1 miles (a 5K) in 28 minutes and 0 seconds. Dividing time by distance gives a pace of about 9 minutes and 2 seconds per mile (28 / 3.1 = 9.03 minutes, or 9:02).
Using that same pace, a 10K (6.2 miles) would take roughly 56 minutes, and a half marathon (13.1 miles) would take about 118 minutes, or 1 hour 58 minutes, assuming the pace stays constant throughout.
Carrying the same 9:02-per-mile pace out to a full marathon (26.2 miles) projects a finish time of about 236 minutes, or roughly 3 hours 56 minutes, though in practice most runners slow somewhat over that distance rather than holding a flat pace for four hours. Comparing these projected times side by side is a common way to gauge whether a goal marathon pace is realistic based on recent shorter-race performance, or to set intermediate split targets for a long training run.
Frequently asked questions
Does pace calculator work for both running and walking?
Yes. The math is identical for any activity measured in distance over time, so it works equally well for walking, running, cycling at a steady rate, or even swimming, as long as you use appropriate distance units.
Why does my actual finish time differ from the calculated one?
The calculation assumes a perfectly even pace for the entire distance. Real-world factors like hills, fatigue, weather, and pacing strategy usually cause your actual splits to vary, so treat the result as a target rather than a guarantee.
Can I convert between minutes-per-mile and minutes-per-kilometer?
Yes, as long as the calculator accepts both units. Since a mile is about 1.609 kilometers, a pace in minutes per mile is generally slower in the raw number than the same effort expressed per kilometer.
How do I use this to plan negative splits?
Calculate your overall goal pace first, then compute times for each segment at a slightly slower pace than goal for the first half and a slightly faster pace for the second half, keeping the total time equal to your target.
Is average pace the same as the pace at any single point in a run?
No. Average pace reflects total time divided by total distance, smoothing out variations. Your pace at any given mile marker could be faster or slower than the average, especially if effort changes over the course.