Running pace·6:38 /km
6:38
/km · 9.05 km/h

6:38 per km — marathon in 4:39:54, 9.05 km/h

Running 6:38 per kilometre is 9.05 km/h. Hold it and the half comes in at 2:19:57, the marathon at 4:39:54.

Finish times

These assume you hold the pace from gun to tape. Most runners drift slower in the second half, so leave a margin when setting a target.

5K
33:10
10K
1:06:20
Half
2:19:57
Marathon
4:39:54
Speed
9.05 km/h
Metres per second
2.513 m/s
Pace per mile
10:41
One lap (400 m)
2:39

What this pace breaks

The cut-offs are tighter than they look: a sub-4 marathon needs 5:41 per kilometre, and one second slower puts you over four hours.

sub-20 min 5K · nosub-25 min 5K · nosub-30 min 5K · nosub-50 min 10K · nosub-60 min 10K · nosub-100 min Half · nosub-2h Half · nosub-3h Marathon · nosub-3:30h Marathon · nosub-4h Marathon · nosub-5h Marathon · yes

Nearby paces

Pace per kmHalfMarathon
6:332:18:114:36:23
6:342:18:324:37:05
6:352:18:544:37:47
6:362:19:154:38:29
6:372:19:364:39:11
6:382:19:574:39:54
6:392:20:184:40:36
6:402:20:394:41:18
6:412:21:004:42:00
6:422:21:214:42:42
6:432:21:424:43:25

The half and the full are not round numbers

A marathon is 42.195 km and a half is 21.0975 km. Rounding to 42 km costs you about a minute at a 5:00 pace — small, but enough to miss a target.

How to read this

  • Pace is the time for one kilometre, so a smaller number means faster.
  • To get speed, divide 3600 by the pace in seconds: 300 s gives 12 km/h.
  • A finish time is simply the pace multiplied by the distance.
  • Mile pace is kilometre pace times 1.609344.

Frequently asked questions

Q. What marathon time does 6:38 per km give?

4:39:54. The half comes in at 2:19:57, the 10K at 1:06:20 and the 5K at 33:10.

Q. How fast is 6:38 per km in km/h?

9.05 km/h, or 2.513 metres per second.

Q. What is that per mile?

10:41, because a mile is 1.609344 km.

Q. And one lap of the track?

2:39 for 400 m.