Convert any distance from kilometres into miles, with the working shown, the answer also given in miles and yards, and a quick conversion table. One kilometre is 0.621371 miles, and a mile is exactly 1.609344 km.
Divide the distance in kilometres by 1.609344, the exact number of kilometres in a mile. Multiplying by 0.621371 gives the same answer to six decimal places.
Miles: Kilometres ÷ 1.609344 ≈ Kilometres × 0.621371
1 km = 0.621371 mi
1 mi = 1.609344 km
0.01 km = 0.006214 mi
0.1 km = 0.062137 mi
1 km = 0.621371 mi
2 km = 1.242742 mi
3 km = 1.864114 mi
4 km = 2.485485 mi
5 km = 3.106856 mi
6 km = 3.728227 mi
7 km = 4.349598 mi
8 km = 4.97097 mi
9 km = 5.592341 mi
10 km = 6.213712 mi
20 km = 12.427424 mi
30 km = 18.641136 mi
40 km = 24.854848 mi
50 km = 31.06856 mi
60 km = 37.282272 mi
70 km = 43.495983 mi
80 km = 49.709695 mi
90 km = 55.923407 mi
100 km = 62.137119 mi
The kilometres to miles calculator converts a metric distance into the imperial mile, which is still used on roads in the United States and the United Kingdom. It multiplies the distance in kilometres by 0.621371, so 10 km becomes about 6.21 miles.
In India almost everything is measured in kilometres: road signs, odometers, railway charts and running apps. The conversion matters when you deal with the rest of the world. A student heading to the US needs to read speed limits in miles per hour, a runner comparing a 21.1 km half marathon with a British race series sees it listed as 13.1 miles, and a cyclist following an international training plan finds weekly volume given in miles.
1. Write the distance in kilometres. If you have metres, divide by 1000 first.
2. Multiply by 0.621371: Miles = Kilometres × 0.621371.
3. For a quick mental check, multiply by 5 and divide by 8. This gives a result about 0.6% high.
4. Round to a sensible number of decimals: one or two for travel, more for surveying or science.
5. To convert a speed, use the same factor, since km/h × 0.621371 gives miles per hour.
Since 1959 the international yard has been defined as exactly 0.9144 metres, and a mile is 1,760 yards. So one mile is exactly 1,609.344 metres, or 1.609344 km. Going the other way, one kilometre is 1 ÷ 1.609344 miles, which works out to 0.621371192... The calculator uses 0.621371, which is accurate to better than one part in a million, far more precise than any road or running distance needs.
Multiplying by 0.6 is easy but runs about 3.4% low: 100 km becomes 60 miles against a true 62.1. Using 5/8, or 0.625, runs about 0.6% high and is the better shortcut. A neat trick uses consecutive Fibonacci numbers: 5 miles is about 8 km, 8 miles is about 13 km, and 13 miles is about 21 km. It works because the ratio of successive Fibonacci numbers approaches 1.618, close to 1.609.
The mile on road signs is the statute mile of 1,609.344 metres. Ships and aircraft use the nautical mile, defined as exactly 1,852 metres, because it corresponds to one minute of latitude on the Earth. A distance in kilometres converts to far fewer nautical miles than statute miles. This calculator gives statute miles, so do not use it for flight or sea distances, and note that knots are nautical miles per hour.
Sneha has just finished her first half marathon of 21.0975 km in Hyderabad and wants to log it in an app set to miles.
Answer: Miles 13.109379
Dividing by 0.621371 instead of multiplying, which gives a bigger number of miles than kilometres. Miles are longer, so the number must get smaller.
Using the 0.6 shortcut for long distances, where the 3.4% shortfall on 500 km is about 11 miles.
Confusing statute miles with nautical miles when reading airline or shipping figures.
Converting a speed limit and then rounding it up, which can put you just over the real limit abroad.
Reading distances and speed limits when driving in the US or UK.
Comparing race distances such as 5K, 10K and half marathons with plans written in miles.
Converting cycling and walking logs between apps that use different units.
Understanding travel, fitness or science articles written for an American audience.
How many miles are in a kilometre?
1 km = 0.621371 miles (1 ÷ 1.609344).
How many miles is 5 km, 10 km, a half marathon or a marathon?
5 km = 3.107 mi, 10 km = 6.214 mi, a half marathon (21.0975 km) = 13.109 mi and a marathon (42.195 km) = 26.219 mi.
How do I convert km/h to miles per hour?
Use the same factor: km/h ÷ 1.609344 = mph. So 100 km/h is about 62.14 mph.
Why is the conversion number not a round number?
A mile and a kilometre are each defined on their own (a mile is exactly 1,609.344 metres), so the conversion number between them is not a round figure.