How the conversion works
Pace is time per distance; speed is distance per time. They're the same information written two ways, so every conversion comes down to two constants: a mile is exactly 1.609344 km, and an hour is 3,600 seconds.
min/mile = min/km × 1.609344 km/h = 3600 ÷ seconds per km
Everything on this page is calculated from seconds per kilometre and converted at the last step, so going from mph to min/km and back returns the number you started with. Paces are rounded to the nearest second and speeds to two decimals.
When you need each unit
- min/km or min/mile for road running. It's what race markers, pace bands and most watches use. Europe and Australia race in kilometres; US races mostly mark miles.
- km/h or mph for treadmills and for comparing with cycling. A treadmill set to 12 km/h is 5:00 per km; 7.5 mph is 8:00 per mile.
- Finish times tell you what a pace means over a real race. Holding 4:44 per km for a marathon, for example, finishes in 3:19:43.
Treadmill belts are rarely perfectly calibrated and there's no wind resistance indoors, so the same number can feel easier on a treadmill than outdoors. Use the conversion for the maths and your breathing for the effort.
Switching units is where a lot of race-day pacing goes wrong. If you trained in min/km and your race marks miles, or the other way round, convert before the start and write the result on your pace band instead of doing the maths at 30 km.
Mental maths for mid-run
No phone? These shortcuts are close enough to use at race effort:
- 10 seconds per km ≈ 16 seconds per mile. Going from 5:00 to 4:50 per km takes about 16 seconds off every mile, and roughly 7 minutes off a marathon.
- min/km to min/mile: add 60 %. 5:00 per km × 1.6 = 8:00 per mile; the exact answer is 8:03.
- Speed to pace: divide 60 by the speed. 60 ÷ 12 km/h = 5 minutes per km; 60 ÷ 8 mph = 7.5, so 7:30 per mile.
- Finish time: pace × distance. 5:00 per km for 10 km is 50 minutes. For a half marathon use 21.1 km: 5:00 per km finishes in 1:45:29.
Pace conversion chart
Common paces from 3:00 to 7:30 per km, with the matching marathon time, plus the marathon world-record paces. Tap a pace to load it above.
| /km | /mile | km/h | mph | Marathon |
|---|---|---|---|---|
| 2:50World record · MenSabastian Kimaru Sawe, 1:59:30 | 4:33 | 21.2 | 13.2 | 1:59:30 |
| 3:00 | 4:50 | 20 | 12.4 | 2:06:35 |
| 3:05World record · WomenRuth Chepngetich, 2:09:56 | 4:57 | 19.5 | 12.1 | 2:09:56 |
| 3:13Women-only recordTigst Assefa, 2:15:41 | 5:11 | 18.7 | 11.6 | 2:15:41 |
| 3:15 | 5:14 | 18.5 | 11.5 | 2:17:08 |
| 3:30 | 5:38 | 17.1 | 10.7 | 2:27:41 |
| 3:45 | 6:02 | 16 | 9.9 | 2:38:14 |
| 4:00 | 6:26 | 15 | 9.3 | 2:48:47 |
| 4:15 | 6:50 | 14.1 | 8.8 | 2:59:20 |
| 4:30 | 7:15 | 13.3 | 8.3 | 3:09:53 |
| 4:45 | 7:39 | 12.6 | 7.8 | 3:20:26 |
| 5:00 | 8:03 | 12 | 7.5 | 3:30:59 |
| 5:15 | 8:27 | 11.4 | 7.1 | 3:41:31 |
| 5:30 | 8:51 | 10.9 | 6.8 | 3:52:04 |
| 5:45 | 9:15 | 10.4 | 6.5 | 4:02:37 |
| 6:00 | 9:39 | 10 | 6.2 | 4:13:10 |
| 6:15 | 10:04 | 9.6 | 6 | 4:23:43 |
| 6:30 | 10:28 | 9.2 | 5.7 | 4:34:16 |
| 6:45 | 10:52 | 8.9 | 5.5 | 4:44:49 |
| 7:00 | 11:16 | 8.6 | 5.3 | 4:55:22 |
| 7:15 | 11:40 | 8.3 | 5.1 | 5:05:55 |
| 7:30 | 12:04 | 8 | 5 | 5:16:28 |