Quick answer: One inch is exactly 2.54 cm and one mile is exactly 1.609344 km, so 10 km = 6.2137119 mi.
How it's calculated
The value is first changed to metres, then from metres to the unit you want. Every factor here is exact by definition: since 1959 the international inch is 25.4 mm, the foot 0.3048 m, the yard 0.9144 m and the mile 1,609.344 m.
A nautical mile, used at sea and in aviation, is exactly 1,852 m. Gulf road signs and car speedometers use kilometres; miles appear mainly on UK and US cars and maps.
Worked examples
- Height of 6 feet: 6 ft = 1.8288 m
- 100 km road trip: 100 km = 62.137119 mi
- Phone screen of 6.1 inches: 6.1 in = 15.494 cm
Common length conversions
| From | To |
|---|---|
| 1 in | 2.54 cm |
| 1 ft | 30.48 cm |
| 1 yd | 0.9144 m |
| 1 mi | 1.609344 km |
| 1 nmi | 1.852 km |
| 1 m | 3.2808399 ft |
| 1 km | 0.62137119 mi |
| 10 cm | 3.9370079 in |
| 100 km | 62.137119 mi |
| 6 ft | 1.8288 m |
Frequently asked questions
How many centimetres are in an inch?
Exactly 2.54 cm. To go from inches to cm multiply by 2.54; from cm to inches divide by 2.54.
How many feet are in a metre?
One metre is about 3.28084 feet (1 ÷ 0.3048).
What is the difference between a mile and a nautical mile?
A statute mile is 1,609.344 m; a nautical mile is 1,852 m, based on one minute of latitude, and is used for ships and aircraft.
How many kilometres are in a mile?
1.609344, exactly. In your head, multiply miles by 1.6, or kilometres by 0.62 to go the other way.
How tall is 5 ft 10 in in centimetres?
177.8 cm. Five feet ten is 70 inches, and each inch is 2.54 cm.
Is a metre longer than a yard?
A little. A metre is 1.0936 yards, so about 8.6 cm longer.