CM to Inches: The Simple Conversion Guide
How to convert centimeters to inches (and back) with the exact formula, a quick reference table, and a free instant converter.
Converting centimeters to inches comes up constantly — screen sizes, clothing, furniture, DIY projects. The math is simple, and you can also just use a free tool to do it instantly.
The formula
1 inch = 2.54 centimeters (exactly)
So to convert:
- CM → inches: divide the number of centimeters by 2.54.
- Inches → CM: multiply the number of inches by 2.54.
Example: 30 cm ÷ 2.54 = 11.81 inches.
Quick reference table
| Centimeters | Inches |
|---|---|
| 1 cm | 0.39 in |
| 5 cm | 1.97 in |
| 10 cm | 3.94 in |
| 20 cm | 7.87 in |
| 30 cm | 11.81 in |
| 50 cm | 19.69 in |
| 100 cm | 39.37 in |
Convert any value instantly
Rather than reaching for a calculator, use the free Length Converter — type any value and it converts between cm, inches, feet, meters, miles and more, with a full conversion table.
Related converters
- Weight Converter — kg to lbs, grams to ounces.
- Temperature Converter — Celsius to Fahrenheit.
- Speed Converter — km/h to mph.
A note on precision
Because 1 inch is defined as exactly 2.54 cm, these conversions are precise — there's no rounding built into the definition. Any rounding you see is just for readability. For exact engineering or manufacturing work, keep the full decimal value from the converter rather than the rounded table above.