How to use the converter
- Type the value. Commas and decimal points both work.
- Choose the unit you have under From and the unit you want under To. The quick buttons set common pairs in one tap.
- Read the result. The table below shows the same value in every unit, and Copy puts the result on your clipboard.
The formulas
Every conversion uses a fixed factor. Since 1959 the inch is defined as exactly 2.54 cm, so all imperial lengths have exact metric values.
- cm to inches: divide by 2.54
- inches to cm: multiply by 2.54
- feet to meters: multiply by 0.3048 (1 ft = 12 in)
- miles to km: multiply by 1.609344 (1 mi = 5,280 ft)
Conversion charts
| Centimeters | Inches |
|---|---|
| 1 cm | 0.39 in |
| 2 cm | 0.79 in |
| 5 cm | 1.97 in |
| 10 cm | 3.94 in |
| 15 cm | 5.91 in |
| 20 cm | 7.87 in |
| 30 cm | 11.81 in |
| 50 cm | 19.69 in |
| 100 cm | 39.37 in |
| 150 cm | 59.06 in |
| 180 cm | 70.87 in |
| Inches | Centimeters |
|---|---|
| 1 in | 2.54 cm |
| 2 in | 5.08 cm |
| 3 in | 7.62 cm |
| 4 in | 10.16 cm |
| 5 in | 12.7 cm |
| 6 in | 15.24 cm |
| 8 in | 20.32 cm |
| 10 in | 25.4 cm |
| 12 in | 30.48 cm |
| 24 in | 60.96 cm |
| 36 in | 91.44 cm |
| Feet | Meters |
|---|---|
| 1 ft | 0.305 m |
| 2 ft | 0.61 m |
| 3 ft | 0.914 m |
| 5 ft | 1.524 m |
| 6 ft | 1.829 m |
| 10 ft | 3.048 m |
| 20 ft | 6.096 m |
| 50 ft | 15.24 m |
| 100 ft | 30.48 m |
| Kilometers | Miles |
|---|---|
| 1 km | 0.62 mi |
| 5 km | 3.11 mi |
| 10 km | 6.21 mi |
| 21.098 km | 13.11 mi |
| 42.195 km | 26.22 mi |
| 100 km | 62.14 mi |
Good to know
Screens are measured diagonally in inches: a 55-inch TV is about 140 cm across the diagonal, a 27-inch monitor about 69 cm. Height in feet and inches: 5 ft 10 in is 177.8 cm. A half marathon is 21.0975 km, about 13.1 miles; a marathon 42.195 km, about 26.2 miles.
Frequently asked questions
How many cm is one inch?
Exactly 2.54 cm. That definition has applied internationally since 1959.
How do I convert my height from feet to cm?
Multiply the feet by 30.48 and the inches by 2.54, then add them. 5 ft 8 in = 152.4 + 20.32 = 172.7 cm.
What is the difference between a mile and a nautical mile?
A statute mile is 1,609.344 m, a nautical mile 1,852 m. Nautical miles are used at sea and in aviation.