How to calculate running pace
Pace is simply how long it takes you to cover one unit of distance — one kilometre or one mile. From a time and a distance you can get pace, speed and a finish-time estimate with a handful of exact arithmetic steps. Here are the formulas, a standard-distance table, and a worked example you can check by hand.
Open the Running Pace calculatorWant the answer without the arithmetic? The Running pace calculator turns any two of time, distance and pace into the third, and shows both min/km and min/mile side by side.
What pace actually is
Pace is the inverse of speed: instead of “distance per unit of time” it is “time per unit of distance”. Runners prefer it because it is easy to hold in your head during a race — “five-minute kilometres” is more actionable than “twelve kilometres an hour”. The only inputs you need are a total time and a total distance; everything else is division.
The core formulas
Work in seconds for the time and keep the distance in the unit you want the pace in. These four expressions cover almost every pace question:
- time_seconds
- total elapsed time converted to seconds (min × 60 + sec)
- distance_km / distance_miles
- the distance covered in the matching unit
- pace_seconds_per_unit
- pace expressed in seconds per km or per mile
- 1 mile
- exactly 1.609344 km — the definition used for every conversion here
Dividing by 60 at the end converts seconds-per-unit into the familiar minutes-and-seconds display. To convert a min/km pace to min/mile, multiply the seconds-per-km value by 1.609344; to go the other way, divide by 1.609344.
Worked example
Suppose you run 10 km in 50:00.
- Convert the time:
50:00 = 3000 s. - Pace:
3000 / 10 / 60 = 5.0 min/km = 5:00 min/km. - Speed:
10 / (3000 / 3600) = 10 / 0.8333 = 12 km/h. - In miles:
5:00 min/km × 1.609344 = 300 s × 1.609344 = 482.8 s = 8:03 min/mile.
Every step is reversible: if you knew you wanted to average 5:00 min/km over 10 km, the
finish-time formula gives 300 × 10 = 3000 s = 50:00.
Standard-distance finish times
The four road distances below use the official course lengths. The table shows the finish time you would post at two round paces — 5:00 min/km and 6:00 min/km — so you can see how pace scales across distance.
| Distance | Length | At 5:00 min/km | At 6:00 min/km |
|---|---|---|---|
| 5K | 5.0000 km | 25:00 | 30:00 |
| 10K | 10.0000 km | 50:00 | 1:00:00 |
| Half marathon | 21.0975 km | 1:45:29 | 2:06:35 |
| Marathon | 42.195 km | 3:30:59 | 4:13:10 |
These come straight from the finish-time formula. For the half marathon at 5:00 min/km:
300 s/km × 21.0975 km = 6329.25 s = 1:45:29. The marathon at 6:00 min/km is
360 × 42.195 = 15190.2 s = 4:13:10.
What this calculation does not tell you
Pace arithmetic assumes you cover the distance at a constant speed and that the course is exactly the stated length. Real runs vary: hills, wind, GPS drift and the fact that you rarely take the shortest legal line all move your measured pace around. A finish-time estimate from an even split also ignores fatigue — holding 5:00 min/km for 10 km says little about whether you can hold it for a marathon. For that, use a race-time predictor, which models slowdown over distance.
Frequently asked questions
How do I convert min/km to min/mile?
Multiply the pace in seconds per kilometre by 1.609344. A 5:00 min/km pace is 300 s, and 300 × 1.609344 = 482.8 s, which is 8:03 min/mile.
What is the difference between pace and speed?
They are inverses. Speed is distance per unit time (km/h); pace is time per unit distance (min/km). At 12 km/h your pace is 5:00 min/km — the same effort described two ways.
Why keep time in seconds?
Working in seconds avoids the errors that creep in when you mix minutes and seconds in the same division. Convert to seconds first, divide, then convert the result back to minutes and seconds.
Related tools and reading
Running pace calculator
Enter any two of time, distance and pace and read the third in both min/km and min/mile.
ReadMarathon pace chart by finish time
The pace you need to hold for every common marathon target, from 3:00 to 5:00.
Sources
- World Athletics, Competition and Technical Rules — official road-race course distances (5 km, 10 km, half marathon 21.0975 km, marathon 42.195 km). Checked 23 Aug 2026.
- International yard and pound agreement (1959) — 1 mile = 1.609344 km exactly, the conversion factor used throughout this page. Checked 23 Aug 2026.