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Length

Inches to Centimeters Converter

Convert lengths in inches to centimeters for product dimensions, craft measurements, print layouts, and metric specifications.

Instant resultAdjustable assumptionsNo data sent
Instant conversion

in cm

Runs in your browser
centimeters2.54cm

Result rounded to a maximum of six decimal places.

Conversion rulecm = inches × 2.54

1 inch = exactly 2.54 cm.

01
Method

How to convert inches to centimeters

Multiply inches by 2.54. The international inch is defined as exactly 2.54 centimeters.

Formulacm = inches × 2.54

1 inch = exactly 2.54 cm.

02
Worked example

Convert 12 in to cm

Apply the conversion rule to 12 inches. Using the default settings, the result is 30.48 cm.

12 in30.48 cm
03
Quick reference

in to cm conversion table

These pre-calculated values use the same formula and default settings as the converter above.

Common inches to centimeters conversions
inches (in)centimeters (cm)
1 in2.54 cm
2 in5.08 cm
3 in7.62 cm
4 in10.16 cm
5 in12.7 cm
6 in15.24 cm
8 in20.32 cm
10 in25.4 cm
12 in30.48 cm
18 in45.72 cm
24 in60.96 cm
36 in91.44 cm
48 in121.92 cm
04
Practical use

Code and calculation snippets

Reuse the same conversion in a stylesheet or application. Keep contextual font sizes configurable when working with relative CSS units.

JavaScript
const centimeters = inches * 2.54;
Python
centimeters = inches * 2.54
05
Interpretation

Using the result accurately

Match the displayed precision to the source measurement. A dimension given to the nearest inch normally should not be reported to many decimal places in centimeters.

Important limitation

The mathematical factor is exact, but real-world measurements may include tolerance and rounding that the converter cannot infer.

Reference: NIST Guide to the SI: conversion factors.

Common questions

Inches to Centimeters Converter FAQ

Short answers about the formula, assumptions, and displayed precision.

How do I convert inches to centimeters?

Multiply inches by 2.54. The international inch is defined as exactly 2.54 centimeters. For example, 12 in converts to 30.48 cm using the default settings.

What formula does this in-to-cm converter use?

cm = inches × 2.54. 1 inch = exactly 2.54 cm.

What assumptions does the calculator make?

The converter uses the fixed relationship described in the formula: 1 inch = exactly 2.54 cm.

How many decimal places should I use?

The calculator shows up to six decimal places and removes unnecessary trailing zeros. Keep more precision for further calculations, then round the final value to suit your measurement or design system.