Centimeters to Inches Converter
Convert centimeters to inches instantly and back. Uses the exact 0.393701 inches per cm factor, with worked examples, a size chart and common cm to in conversions.
Updated 2026-06-14 · Free · No sign-up · Runs privately in your browser
Show the formula & steps
How the Centimeters to Inches Converter Works
This converter switches between centimeters (cm) and inches (in) in both directions, using the exact factor of 2.54 cm per inch. Type a value, pick the direction, and the answer updates live with the steps shown.
The Formula
Inches = centimeters ÷ 2.54 (equivalently, inches ≈ centimeters × 0.393701)
Because the inch is defined as exactly 2.54 cm, this conversion has no built-in rounding error. To convert inches back to centimeters, multiply by 2.54 instead.
Worked Example
Convert 30 centimeters to inches:
- 30 ÷ 2.54 = 11.81 inches
Convert 15 inches to centimeters:
- 15 × 2.54 = 38.10 cm
Common Sizes Reference Chart
| Centimeters | Inches |
|---|---|
| 5 | 1.97 |
| 10 | 3.94 |
| 30 | 11.81 |
| 50 | 19.69 |
| 100 | 39.37 |
Where You Will Use It
Centimeter-to-inch conversions appear in clothing and shoe sizes, furniture dimensions, screen and photo sizes, and any project where metric measurements meet inch-based tools. Since the factor is exact, you can convert freely in either direction with no accumulated error.
Frequently asked questions
How many inches are in a centimeter?+
One centimeter equals about 0.393701 inches. So 1 inch is exactly 2.54 cm, by international definition.
How do I convert centimeters to inches?+
Divide the number of centimeters by 2.54 (or multiply by 0.393701). For example, 30 cm ÷ 2.54 = 11.81 inches.
How many inches is 30 cm?+
30 centimeters equals about 11.81 inches. Divide 30 by 2.54 to get the precise value of 11.811 inches.
How many inches is 100 cm?+
100 centimeters (one meter) equals about 39.37 inches. Divide 100 by 2.54 to confirm the figure of 39.370 inches.
Is the cm to inch conversion exact?+
The defining relationship (1 inch = 2.54 cm) is exact, so converting cm to inches is exact too — though the decimal result 0.393701 is usually rounded for display.