“I ran a 5:30 pace” means something different in Berlin and in Boston, because one runner is thinking per kilometre and the other per mile. The calculation is simple; the unit is where the confusion creeps in.
The calculation
Pace is total time divided by distance. A 5 km run in 27 minutes 30 seconds is 1,650 seconds over 5 km, which is 330 seconds per kilometre, or 5:30 per km. To get pace per mile, divide the time by the distance in miles instead. One mile is 1.609344 km, so 5 km is about 3.107 miles, and 1,650 divided by 3.107 gives 531 seconds, or 8:51 per mile.
Using the calculator
- Open the Pace Calculator.
- Enter your time as minutes and seconds (27:30) or with hours for longer efforts (1:55:00).
- Enter the distance and choose kilometres or miles.
- Read the pace per km and per mile together.
Three race examples
| Effort | Time | Pace per km | Pace per mile |
|---|---|---|---|
| 5K (5 km) | 27:30 | 5:30 | 8:51 |
| 10K (10 km) | 52:00 | 5:12 | 8:22 |
| Half marathon (21.0975 km) | 1:55:00 | 5:27 | 8:46 |
A handy shortcut: pace per mile is about 1.6 times the pace per km. The half-marathon figure also shows why you should enter the exact distance. Rounding 21.0975 km to 21 km would shift the answer by a couple of seconds per kilometre.
Using pace on race day
To find the finish time for a target pace, multiply it by the distance. A 5:30 pace over a marathon (42.195 km) comes to about 3 hours 52 minutes. Many runners aim for an even pace or a slightly faster second half, since going out too fast is the most common reason people fade late.
Why your watch may disagree
GPS watches estimate distance from satellite signals and can read a little long or short, especially among tall buildings or trees. A treadmill measures belt speed, which may be slightly off. For a fixed-distance race, trust the official course length and your official time, and use the calculator to see what pace that really was.
If you are new to running or returning after a break, build up gradually, and check with a doctor first if you have a heart or joint condition. Pace is a measurement, not a training plan.
Frequently asked questions
How do I convert pace per kilometre to pace per mile?
Multiply by 1.609344. A 5:30 per km pace is 330 seconds × 1.609344 = 531 seconds, or 8:51 per mile.
What is a good running pace?
It depends on age, training, terrain and weather, so there is no single answer. Compare yourself with your own earlier runs rather than with a headline figure.
Do hills change my pace?
Yes. Uphill sections slow you and downhill ones speed you up, so average pace on a hilly course is not comparable with a flat one. Many runners use effort, not pace, on hills.