Quick answer: Running 10 km in 50 minutes is a pace of 50 ÷ 10 = 5:00 per km, which is 8:03 per mile or 12 km/h; at that pace a half marathon takes 1:45:29.
How it's calculated
Pace is time divided by distance; time is pace × distance; distance is time ÷ pace. Speed is the inverse of pace: 3,600 seconds ÷ seconds per km gives km/h. One mile is 1.609344 km.
Race times in the table assume an even pace over the official distances: 5 km, 10 km, 21.0975 km for the half marathon and 42.195 km for the marathon.
The numbers cannot predict how your pace holds up over a longer race: most runners slow as the distance grows, and heat, humidity and hills slow everyone. In Gulf summers, plan for slower times or run early.
Worked examples
- 10 km in 50:00: 3000 s ÷ 10 = 300 s = 5:00 /km (8:03 /mi)
- Marathon at 5:00 /km: 300 s × 42.195 = 3:30:59
- 1 hour at 6:00 /km: 3600 ÷ 360 = 10 km
Pace and speed
| Pace per km | Pace per mile | Speed |
|---|---|---|
| 4:00 | 6:26 | 15 km/h |
| 5:00 | 8:03 | 12 km/h |
| 6:00 | 9:39 | 10 km/h |
| 7:00 | 11:16 | 8.57 km/h |
Frequently asked questions
What is a good running pace?
For many recreational runners, easy runs sit around 6 to 7 minutes per km. Age, training and distance all shift that, and a pace you can hold for the whole session matters more than the number.
How do I convert pace per km to pace per mile?
Multiply the pace per km by 1.609344. For example, 5:00 per km × 1.609344 = 8:03 per mile.
Why is my race time slower than the table?
The table assumes an even pace. Fatigue, crowds at the start, hills and heat all add time over a long race.
How long does a marathon take at my pace?
Multiply your pace by 42.195 km. At 5:00 per km that is 3 hours 30 minutes 58 seconds, if you can hold that pace to the finish.
How do I set a treadmill for a given pace?
Divide 60 by your minutes per km to get km/h. A 5:00 pace is 60 ÷ 5 = 12 km/h, and a 6:00 pace is 10 km/h.
What is a negative split?
Running the second half of a race faster than the first. Many runners aim for it, because starting too fast usually costs more time later.