Endurometry
Pace is time divided by distance. A 5 km in 25:00 is 5:00/km, about 8:03 per mile. Speed is the inverse (12.00 km/h). Use one unit and convert; do not mix them mid-race.
Last updated October 5, 2026
Runners talk in pace because a watch split is a time, and a kilometre marker is a distance. Pace = time ÷ distance. Speed is the inverse: distance ÷ time. Both describe the same run; they are not two fitness scores.
The definition
If you cover D kilometres in T minutes, pace in min/km is T ÷ D. The pace calculator does that arithmetic and also shows min/mile, km/h and mph. It is an exact conversion aside from rounding the display to a whole second.
A worked example (same numbers as the calculator)
Default-style check: 5 km in 25:00.
- 25 minutes ÷ 5 km = 5:00/km
- 1 mile = 1.609344 km, so 5:00/km × 1.609344 = 8:03/mi (8.04672 min, shown as 8:03)
- Speed: 5 km / (25/60) h = 12.00 km/h ≈ 7.46 mph
A 10 km in 50:00 is the same 5:00/km. A marathon in 4:00:00 is 5:41/km (9:09/mi) because 240 min ÷ 42.195 km ≈ 5.688 min/km.
Pace is not the split you just ran
Average pace is the whole race. Kilometre 1 at 4:40 and kilometre 10 at 5:20 can still average 5:00. GPS watches also add extra metres on corners. Treat the number as a mean, then use race splits if you need clock times at each marker.
min/km versus min/mile
The factor is always 1.609344 (international mile). min/mile = min/km × 1.609344. The pace converter also turns a 400 m track split into a pace. A 2:12 400 m is 5:30/km because 400 m is 0.4 km and 2.2 min / 0.4 = 5.5 min/km.
How to use it on a Tuesday
Pick the unit your markers use. Road races in most of the world are kilometres; many US plans are miles. Convert once, then run. For a printable grid in both units, open the pace chart generator. Rounding rules live on the methodology page.
Related Tools
Running Pace Calculator
Enter distance and finish time to get your pace per km and mile, average speed and per-kilometre splits.
Running Pace Converter
Convert between min/km, min/mi, km/h and mph, and see the implied finish time for 5K, 10K, half marathon and marathon.
Pace Chart Generator
Enter a goal finish time and get a pace chart in both min/km and min/mile, a speed-to-pace conversion table, your tempo pace and a printable wristband.
Related guides
Pace vs Speed
Pace is minutes per kilometre or mile. Speed is kilometres or miles per hour. Same run, inverse units — and the converter uses the same numbers as this page.
min/km ↔ min/mile
Convert min/km and min/mile with the international mile 1.609344 km. Why 5:00/km is 8:03/mi, not 8:00, and how a 400 m split becomes a pace.
How to Calculate Race Splits
Turn a goal finish into cumulative kilometre or mile splits, including the leftover 42.195 km row, and how that differs from a wrist pace band.
How the numbers are calculated
Pace, speed and distance · Speed and unit conversion · Rounding and displayed precision · Sources
Frequently Asked Questions
Is 5:00/km the same as 12 km/h?
Yes, if you hold it exactly. 60 ÷ 5 = 12. Display rounding can hide a fraction of a second.
Why is my watch different from the calculator?
The calculator uses the distance you typed. The watch uses GPS, which is usually long, plus its own rounding.
Should I think in km or miles?
Match the course markers. Convert with 1.609344; do not approximate 1.6 in a marathon or the last kilometres drift.
Does pace include hills?
Not in this definition. Grade belongs in the treadmill and calorie tools, not in time ÷ distance.
Want a new tool or fix?
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