Last updated: September 16, 2026
Quick answer: To convert inches to centimeters, multiply the length by 2.54. One inch is exactly 2.54 cm, so 5 inches = 12.7 cm and 12 inches (1 foot) = 30.48 cm.
Inch to Centimeter
Instantly convert inch to centimeter with fast, accurate, real-time results.
Inches and centimeters are the two units most people reach for when a measurement crosses between the imperial and metric systems — a screen size, a piece of furniture, a height, or a sewing pattern. Because the inch is defined directly in terms of the centimeter, converting between them is exact and never an approximation.
How to convert inches to cm
Multiply the number of inches by 2.54 to get centimeters. The inch has been defined as exactly 2.54 centimeters since the international yard-and-pound agreement of 1959, so this is a definition, not a rounded figure.
To go the other way, divide by 2.54 — see the cm to inches converter.
Step-by-step
- Write down the length in inches (for example, 5 in).
- Multiply it by 2.54.
- The result is the length in centimeters (5 × 2.54 = 12.7 cm).
- Round to the precision you need — the calculator above lets you choose the number of digits.
Worked example
Suppose a laptop screen is 15.6 inches on the diagonal and you want it in centimeters:
So a 15.6-inch screen measures about 39.62 cm diagonally.
Inches to cm conversion table
| Inches (in) | Centimeters (cm) |
|---|---|
| 1 in | 2.54 cm |
| 2 in | 5.08 cm |
| 3 in | 7.62 cm |
| 4 in | 10.16 cm |
| 5 in | 12.7 cm |
| 6 in | 15.24 cm |
| 7 in | 17.78 cm |
| 8 in | 20.32 cm |
| 9 in | 22.86 cm |
| 10 in | 25.4 cm |
| 12 in (1 ft) | 30.48 cm |
| 15 in | 38.1 cm |
| 18 in | 45.72 cm |
| 20 in | 50.8 cm |
| 24 in (2 ft) | 60.96 cm |
| 30 in | 76.2 cm |
| 36 in (3 ft / 1 yd) | 91.44 cm |
| 40 in | 101.6 cm |
| 50 in | 127 cm |
| 60 in (5 ft) | 152.4 cm |
| 72 in (6 ft) | 182.88 cm |
| 100 in | 254 cm |
Understanding your result
Because 1 inch = 2.54 cm exactly, the conversion introduces no error of its own — any rounding you see comes only from the number of decimal places you choose to display. For most everyday needs, one or two decimal places is plenty; for engineering or tailoring you may want more. The converter defaults to 6 significant digits and lets you raise or lower that.
Accuracy & limitations
This tool uses the international inch (2.54 cm exactly), which is the standard used almost everywhere today. It is not the US survey inch, a slightly different historical unit used only in some legacy US land-survey data; the difference is about two parts per million and matters only over very large distances. For lengths you would ever measure in inches, the international inch is the correct choice.
Frequently asked questions
How many cm are in an inch?
There are exactly 2.54 centimeters in one inch.
How do I convert inches to cm?
Multiply the length in inches by 2.54. For example, 8 inches × 2.54 = 20.32 cm.
Is 1 inch exactly 2.54 cm?
Yes. Since the 1959 international agreement, the inch is defined as exactly 2.54 cm, so the conversion is exact rather than approximate.
What is 5 inches in cm?
5 inches equals 12.7 cm (5 × 2.54).
What is 12 inches in cm?
12 inches — one foot — equals 30.48 cm.
How do I convert cm back to inches?
Divide the length in centimeters by 2.54. You can use the cm to inches converter for that direction.
Related converters
Creator
Shakeel Muzaffar is the Founder and Editor-in-Chief of MultiCalculators.com, bringing over 15 years of experience in digital publishing, product strategy, and online tool development. He leads the platform's editorial vision, ensuring every calculator meets strict standards for accuracy, usability, and real-world value. Shakeel personally oversees content quality, formula verification workflows, and the platform's commitment to publishing tools that are genuinely useful for students, professionals, and everyday users worldwide.
Areas of Expertise: Editorial Leadership, Digital Publishing, Product Strategy, Online Calculators, Web Standards
