How to Convert Inches to CM - Formula and Examples
Learn the exact inches-to-centimeters formula, work through examples, and avoid common rounding mistakes.
The exact formula
Multiply the inch measurement by 2.54. The factor is exact, so any rounding comes from how the final result is displayed.
Worked example
For 12 inches, calculate 12 × 2.54. The result is exactly 30.48 centimeters. For 5.5 inches, 5.5 × 2.54 = 13.97 centimeters.
When precision matters
Keep extra decimal places while calculating product tolerances, technical drawings, or body measurements. Round only the final result to the precision your task requires.
Related measurement tools
Convert a value with the inches-to-cm converter, use the reverse centimeter converter, or compare common values in the inch-to-cm chart. Popular examples include 10 inches in cm and 12 inches in cm.
Browse the complete inch-to-cm chart →
Frequently asked questions
What is the exact inch-to-cm conversion factor?
One inch is exactly 2.54 centimeters.
Can I use the converter for decimal measurements?
Yes. The converter accepts whole and decimal measurements and displays up to four decimal places.