About this tool
This converter uses the exact international standard: 1 inch equals exactly 2.54 centimeters. Type a value into either field and the other updates instantly — nothing is sent to a server.
Quick reference table
| Centimeters | Inches |
|---|---|
| 1 cm | 0.39 in |
| 5 cm | 1.97 in |
| 10 cm | 3.94 in |
| 15 cm | 5.91 in |
| 30 cm | 11.81 in |
| 100 cm | 39.37 in |
Common use cases
- Converting a product's listed dimensions (common on international or imported items) into a familiar unit
- Checking clothing or shoe measurements between metric and imperial sizing
- Converting a height, screen size, or furniture measurement for a US audience
Things to watch out for
The 2.54 cm-per-inch figure is an exact international definition, not a rounded approximation — so any small differences you see between calculators usually come from how many decimal places the result is rounded to, not the underlying conversion itself. For everyday use, 2 decimal places (as in the table above) is generally precise enough; for scientific or manufacturing work, use the calculator's full unrounded result.
Frequently asked questions
1 centimeter equals 0.3937 inches. This is an exact conversion: 1 inch is defined as exactly 2.54 cm, so 1 cm is exactly 1 ÷ 2.54 inches.
In 1959, the US, UK, and other countries agreed to define the inch as exactly 2.54 centimeters, making it a fixed international standard rather than an approximation. Every cm-to-inch conversion today is based on that exact figure.
The underlying conversion factor (2.54 cm per inch) is exact by international agreement, so the calculator's result is as precise as the number of decimal places you need — it isn't an approximation.