Centimeters to Inches converter
Quick reference
About length units
Length units split into two families: metric (millimeter through kilometer, each a factor of ten apart) and US/imperial (inch, foot, yard, mile, with historical ratios like 12 inches to a foot and 5,280 feet to a mile). The bridge between them was fixed by international agreement in 1959: one inch equals exactly 25.4 millimeters, which makes every metric-imperial length conversion exact rather than approximate. Runners meet this constantly (a 5K is 3.11 miles, a marathon 26.22), as do builders working from plans drawn in the other system.
More length conversions
Frequently asked questions
What is the exact formula for Centimeters to Inches?
Multiply the Centimeters value by 0.39370079. This comes from the exact unit definitions, not a rounded approximation.
Is this conversion exact?
The underlying ratio is exact where a legal definition exists (for example, 1 inch = 25.4 mm exactly). Displayed results are rounded to six decimal places for readability.
Can I convert Inches back to Centimeters?
Yes. Use the reverse converter linked below, or just swap which field you type into: the live converter recalculates either direction.