cm to inches
Nothing you type leaves this device.
The short answer
One centimetre is 0.3937 inches. An inch is defined as exactly 2.54 centimetres, so this is a division rather than a measurement, and nothing is rounded until it reaches the screen.
A conversion is arithmetic, not a service. This page does it in front of you and works with the connection off.
The formula
inches = cm ÷ 2.54
Worked examples
- 10 cm
- 3.94 in
- 30 cm
- 11.81 in
- 6 in
- 15.24 cm
Reference table
| Centimetres | Inches | On a tape measure |
|---|---|---|
| 1 cm | 0.3937 in | 3/8 in |
| 2 cm | 0.7874 in | 13/16 in |
| 5 cm | 1.9685 in | 1 15/16 in |
| 10 cm | 3.937 in | 3 15/16 in |
| 15 cm | 5.9055 in | 5 7/8 in |
| 20 cm | 7.874 in | 7 7/8 in |
| 25 cm | 9.8425 in | 9 13/16 in |
| 30 cm | 11.811 in | 11 13/16 in |
| 50 cm | 19.685 in | 19 11/16 in |
| 100 cm | 39.3701 in | 39 3/8 in |
How to use it
- 01Type into either fieldCentimetres or inches. Both are live, and each rewrites the other as you type.
- 02Read the other oneThe line underneath restates the conversion in words and to two decimal places.
Also searched for
Searches that land here include cm to inches, inches to cm, centimetres to inches, cm to inch converter and convert cm to in.
About the inch
An exact number, not an approximation
Since 1959 the international inch has been defined as exactly 2.54 centimetres, agreed between the national standards bodies of the English-speaking countries. Before that the American and British inches differed very slightly, which caused real problems in precision engineering. So this conversion has no rounding error of its own — only whatever rounding you ask for in the display.
Questions people ask
Why can I type in either field?
Because half the people who search for this are converting the other way, and making one field the input and the other the output would be right for exactly half of them. Both are live and each rewrites the other.