How many inches in a centimetre?

One centimetre is about 0.3937 inches, and one inch is exactly 2.54 centimetres. So to convert centimetres to inches, divide by 2.54. The converter does it both ways as you type.

How do I convert cm to inches?

Divide the number of centimetres by 2.54. For example 30 centimetres is 30 divided by 2.54, which is about 11.81 inches. Enter your value and the converter shows the result instantly.

Why is an inch 2.54 cm exactly?

The inch was defined as exactly 2.54 centimetres by international agreement in 1959, so the conversion is precise rather than approximate.

Cm to Inches Converter

This converter switches lengths between centimetres and inches instantly, both ways, so you never have to reach for a formula halfway through a job. New Zealand uses the metric system for almost everything, but plenty of things you buy or measure, from TV and monitor screen sizes to fabric widths, timber, tyres and imported hardware, are still specified in inches, which makes a quick, accurate converter genuinely useful. You simply type a number into either the centimetres box or the inches box, and the other field updates the moment you stop typing, with no button to press. The maths behind it is exact rather than approximate: one inch is defined as precisely 2.54 centimetres, so centimetres are divided by 2.54 to get inches, and inches are multiplied by 2.54 to get centimetres, giving a result accurate to four decimal places. Below the converter you will also find a quick-reference table showing common values, from 1cm through to 100cm, so you can sanity-check a figure at a glance without typing anything in. Use it for checking whether a piece of furniture will fit through a doorway measured in inches, converting a screen size, or working out fabric or timber lengths sold in imperial units when your tape measure or plans are in centimetres.

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Centimetres

Inches

How it works

Divide centimetres by 2.54 to get inches, or multiply inches by 2.54 to get centimetres. The inch is defined as exactly 2.54 centimetres, so the conversion is exact.

Quick reference

Centimetres	Inches
1	0.39
10	3.94
30	11.81
50	19.69
100	39.37

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Height Calculator: cm to feet and inches.
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Feet to Metres Converter: feet to metres.
Kg to Lbs Converter: weight conversion.

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