Inch to Centimeter Converter
Converts inch to centimeter (in to cm) and back. The conversion factor is shown below every result.
How to Convert Inch to Centimeter
What Is an Inch?
Exactly 25.4 millimeters defines the inch (in), a length unit common to US customary and imperial measurement.
What Is a Centimeter?
The centimeter (cm) is a metric length unit, one hundredth of a meter.
Common Inch to Centimeter Reference Points
Real-world reference values for quick sanity checks.
| Item | Inch (in) | Centimeter (approx.) |
|---|---|---|
| A standard ruler | 12 in | 30.48 cm |
| A basketball's diameter | 9.55 in | 24.26 cm |
| A sheet of A4 paper width | 8.27 in | 21.0 cm |
| Reference values are illustrative approximations for common items, not measured specifications. | ||
Inch to Centimeter Conversion Table
| Inch (in) | Centimeter (cm) |
|---|---|
| 1 in | 2.54 cm |
| 2 in | 5.08 cm |
| 3 in | 7.62 cm |
| 5 in | 12.7 cm |
| 6 in | 15.24 cm |
| 12 in | 30.48 cm |
| 18 in | 45.72 cm |
| 24 in | 60.96 cm |
| 36 in | 91.44 cm |
| 48 in | 121.92 cm |
| Source: NIST SP 811, Appendix B (1 in = 2.54 cm exactly) | |
Frequently Asked Questions
How do I convert inches to centimeters?
Multiply the inch value by 2.54. For example, 10 in × 2.54 = 25.4 cm exactly.
Is the inch-to-centimeter conversion exact or approximate?
It's exact. 1 inch is defined as exactly 2.54 cm, so there's no rounding error in the conversion factor itself. Any imprecision comes only from how many decimal places you keep in your input value.
How do I convert a height in feet and inches to centimeters?
Convert the feet to inches first (multiply by 12), add the remaining inches, then multiply the total inches by 2.54. For example, 5 ft 9 in = 69 in, and 69 × 2.54 = 175.26 cm.
Related Length Converters
A good measuring tool marked in both in and cm removes the guesswork at the point of use.