CM to Inches Converter
Divide a length in centimeters by 2.54 to get inches. 10 cm = 3.93700787402 in, so a 10 cm length is a little under four inches.
Type a value in either box below. Enter centimeters to get inches, or enter inches to get centimeters. Both directions use the same calculation.
Runs in your browser. Conversions are calculated on your own device, and nothing you enter is sent to a server. This page opens the Unit Converter with this conversion selected, so you can change either unit.
Did this tool help you? ☕
WebzTools is free to use. If this tool saved you some time, you can support the project with a coffee and help us keep improving the tools.
(opens in a new tab)How to convert centimeters to inches
Formula: inches = centimeters / 2.54
The constant is exact by definition: 1 inch = 2.54 centimeters. It is not a rounded approximation.
The inch has been defined as exactly 2.54 centimeters since the international yard and pound agreement of 1959, so the relationship itself involves no rounding. Rounding only appears when a result is written out in decimals, because dividing by 2.54 often does not end.
Worked example: 10 cm to inches
The answer below is shown to 12 significant digits. The full value has more digits, so treat the displayed figure as rounded.
Convert 10 cm
Input
10 cm
Output
10 / 2.54 = 3.93700787402 in
Common centimeters to inches conversions
| Centimeters (cm) | Inches (in) |
|---|---|
| 1 cm | 0.393700787402 in |
| 2 cm | 0.787401574803 in |
| 5 cm | 1.96850393701 in |
| 10 cm | 3.93700787402 in |
| 20 cm | 7.87401574803 in |
| 30 cm | 11.811023622 in |
| 50 cm | 19.6850393701 in |
| 100 cm | 39.3700787402 in |
When you need to convert centimeters to inches
- Furniture and product dimensions: a shelf or a screen listed in centimeters, measured against a space in inches.
- Clothing: waist, chest and inseam read from a metric tape, compared with a size chart in inches.
- Print, frame and photo sizes that are quoted in centimeters by one seller and inches by another.
- Everyday metric and imperial measurements, such as a child's height or the width of a window.
Things worth knowing
- A screen's size in inches, such as a 27 inch monitor, is the length of its diagonal. It is not the width or the height, so a width in centimeters will not match the size on the box.
Converting back and related converters
To go the other way, use the Inches to CM Converter, which applies centimeters = inches × 2.54. For any other pair of units, open the Unit Converter, or browse every unit converter.
- MM to Inches Converter: for smaller measurements, such as parts and hardware.
- Meters to Feet Converter: for rooms, heights and other longer lengths.
Frequently asked questions
How many inches are in 1 cm?
1 cm = 0.393700787402 in. That is the reciprocal of 2.54, and it does not end, so the figure is rounded when it is written out in decimals.
Is 2.54 cm exactly 1 inch?
Yes. Since 1959 the inch has been defined as exactly 2.54 centimeters, which is 0.0254 meters. Any rounding you see comes from writing a result in decimals, not from the definition.
How do I convert cm to inches by hand?
Divide by 2.54. For example, 10 / 2.54 on a calculator gives about 3.937. Dividing by 2.5 instead is a rough shortcut that makes the answer about 1.6 percent too high.
Does this give fractions of an inch?
No. Results are decimals. A fraction such as 3 15/16 means rounding to a step like a sixteenth of an inch, which depends on how precise you need to be, and this converter does not round that way.