Min/km to Min/Mile: Pace Conversion for Runners

Your running app says 5:30 per kilometre, but the training plan your friend sent over talks in minutes per mile. Or you are in a US race where every marker is in miles, and your watch is still set to kilometres. Either way, the question is simple: how do you convert min/km to min/mile, and back again, without fumbling the maths mid-run?

The short answer: multiply your per-kilometre pace by 1.609344 to get your per-mile pace, and divide by the same number to go the other way. The rest of this guide shows you how to do that cleanly with minutes and seconds, a quick mental shortcut, a ready-made pace chart, and the mistakes that trip most runners up.

Why the conversion factor is 1.609344

One international mile is defined as exactly 1,609.344 metres, or 1.609344 km. That figure has been fixed by international agreement since 1959, so it is exact, not an approximation. Because a mile is longer than a kilometre, it always takes you longer to run a mile than a kilometre at the same effort. That means:

• Pace per mile = pace per km × 1.609344
• Pace per km = pace per mile ÷ 1.609344 (or × 0.621371)

Notice this is the reverse of how distance converts. Ten kilometres is only 6.21 miles, so distance gets smaller when you switch to miles, but pace gets bigger, because each unit of distance is longer.

How to convert min/km to min/mile, step by step

The only fiddly part is that pace is written in minutes and seconds, which is base 60, not base 10. The cleanest method is to turn everything into seconds first.

1. Convert the pace to seconds. Minutes × 60, plus the seconds.
2. Multiply by 1.609344 (km to mile) or divide by 1.609344 (mile to km).
3. Divide the result by 60. The whole number is your minutes.
4. Turn the remainder back into seconds. Subtract minutes × 60 from your total seconds.
5. Round to the nearest second and write it as m:ss.

Worked example 1: 5:30 per km to per mile

• Step 1: 5 × 60 + 30 = 330 seconds per km
• Step 2: 330 × 1.609344 = 531.08 seconds per mile
• Step 3: 531.08 ÷ 60 = 8.85, so 8 whole minutes
• Step 4: 531.08 − (8 × 60) = 531.08 − 480 = 51.08 seconds
• Step 5: round to 51 seconds

Answer: 5:30 per km is 8:51 per mile.

Worked example 2: 9:00 per mile to per km

• Step 1: 9 × 60 = 540 seconds per mile
• Step 2: 540 ÷ 1.609344 = 335.54 seconds per km
• Step 3: 335.54 ÷ 60 = 5.59, so 5 whole minutes
• Step 4: 335.54 − 300 = 35.54 seconds
• Step 5: round to 36 seconds

Answer: 9:00 per mile is about 5:36 per km.

Worked example 3: planning a 50-minute 10K

Say you want to break 50 minutes for 10 km, but your race is in the US and the course is marked every mile.

• Target pace per km: 50 minutes ÷ 10 km = 5:00 per km = 300 seconds
• Per mile: 300 × 1.609344 = 482.80 seconds
• 482.80 − 480 = 2.80 seconds, so 8:03 per mile
• Race distance in miles: 10 ÷ 1.609344 = 6.21 miles

So you need to hit each mile marker in about 8:03 or a touch under. Going through mile 3 in roughly 24:08 tells you that you are on track.

The mental shortcut: “add 60%”

Mid-run, nobody is multiplying by 1.609344. A good approximation is to multiply by 1.6, which is the same as adding 60%:

• 5:00 per km: 60% of 5 minutes is 3 minutes, so roughly 8:00 per mile (the exact answer is 8:03)
• 6:00 per km: 60% of 6 minutes is 3:36, so roughly 9:36 per mile (exact: 9:39)

Going the other way, multiply your mile pace by about 0.62, or simply take off three-eighths. For 8:00 per mile, 0.62 × 480 seconds is 297.6 seconds, or just under 5:00 per km (exact: 4:58). The shortcut always runs a few seconds fast for per-mile pace, because 1.6 is slightly smaller than 1.609344, so allow an extra 2 to 4 seconds per mile at typical training paces.

Pace conversion chart: min/km, min/mile and race finish times

This table covers the range most recreational runners train in. Speeds are shown too, because treadmills in UK gyms usually display km/h while US gyms tend to use mph. All values are calculated from the exact 1.609344 factor and rounded to the nearest second or hundredth.

Pace per km	Pace per mile	Speed (km/h)	Speed (mph)	5K finish	10K finish	Half marathon	Marathon
4:00	6:26	15.00	9.32	20:00	40:00	1:24:23	2:48:47
4:30	7:14	13.33	8.28	22:30	45:00	1:34:56	3:09:53
5:00	8:03	12.00	7.46	25:00	50:00	1:45:29	3:30:59
5:30	8:51	10.91	6.78	27:30	55:00	1:56:02	3:52:04
6:00	9:39	10.00	6.21	30:00	1:00:00	2:06:35	4:13:10
6:30	10:28	9.23	5.74	32:30	1:05:00	2:17:08	4:34:16
7:00	11:16	8.57	5.33	35:00	1:10:00	2:27:41	4:55:22
7:30	12:04	8.00	4.97	37:30	1:15:00	2:38:14	5:16:28
8:00	12:53	7.50	4.66	40:00	1:20:00	2:48:47	5:37:34

Race distances used: 5K = 3.11 miles, 10K = 6.21 miles, half marathon = 21.0975 km (13.11 miles), marathon = 42.195 km (26.22 miles). Finish times assume perfectly even pacing over the official distance. In a real race your GPS will usually read slightly long because you rarely run the exact racing line, so many runners aim a few seconds per km quicker than the table suggests.

Converting treadmill speed to pace

Treadmills show speed, not pace, so you need one more step. The rule is: pace in minutes per unit = 60 ÷ speed in units per hour.

• 10 km/h: 60 ÷ 10 = 6 minutes per km, which is 360 × 1.609344 = 579.36 seconds, or 9:39 per mile
• 6 mph: 60 ÷ 6 = 10 minutes per mile, which is 600 ÷ 1.609344 = 372.83 seconds, or 6:13 per km

To go from km/h to mph, divide by 1.609344 (10 km/h is 6.21 mph). Our speed converter handles km/h, mph, metres per second and knots if you need other units.

Common pace conversion mistakes

• Treating decimals as seconds. 5.5 minutes is 5:30, not 5:50. If a calculator gives you 8.85 minutes, that is 8 minutes and 51 seconds (0.85 × 60), not 8:85.
• Converting distance instead of pace. Dividing 5:30 by 1.609 gives 3:25, which is a world-class pace. If the per-mile number comes out smaller than the per-km number, you have used the wrong operation.
• Mixing up a track lap. A modern running track is 400 metres, slightly short of a quarter mile (402.3 m). Four laps is 1,600 m, so a “track mile” is about 9 metres short of a true mile, roughly 3 seconds at an 8-minute-mile pace.
• Rounding too early. Round only at the final step. Rounding 1.609344 to 1.6 before a marathon calculation can shift your predicted finish by over a minute.

Frequently asked questions

Is a 5-minute kilometre fast?

A 5:00 per km pace equals about 8:03 per mile and a 25-minute 5K. For many recreational runners that is a solid, achievable goal after a few months of regular training, while experienced club runners often train well below it. What counts as fast depends on your age, experience and the type of run, so compare against your own previous times rather than anyone else’s.

How do I switch my running watch between km and miles?

Most GPS watches let you change units in the system or user settings, and the change applies to pace, distance and speed together. If you only want to check one figure, it is often quicker to use a converter than to swap units, especially mid-plan.

What is a 10-minute mile in km pace?

Ten minutes is 600 seconds. Dividing by 1.609344 gives 372.83 seconds, so a 10:00 mile is about 6:13 per km, which is 9.66 km/h or exactly 6 mph.

Convert any pace instantly

The manual method is worth knowing, but for planning a full training block it is quicker to let a tool do it. Our free athletic pace converter switches between min/km, min/mile and speed in one go, and also works out finish times for any race distance. If you are setting effort levels as well as pace targets, pair it with the heart rate zone calculator so your easy runs stay easy. Both the NHS and the CDC suggest adults aim for around 150 minutes of moderate activity a week, and a sensible pace plan is a good way to build towards that safely.

This article is for general information only and is not medical advice. If you are new to running or have a health condition, speak to your GP or doctor before starting a new training plan.