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Centimeters to inches (cm to in)

To convert centimeters to inches (cm to in): one centimeter is 0.39370079 inches, so 20 cm is 7.87402 in.

Swap units: in to cm

In inches7.87402 in

Conversion factor Exact by definition. The inch has been exactly 2.54 cm and the pound exactly 0.45359237 kg since the 1959 international yard and pound agreement, so these are not measurements that can drift.
1 centimeter = 0.3937007874 inches
The other way
1 inch = 2.54 centimeters
Working
20 x 0.3937007874 = 7.87402
20 cm in every unit
200 mm 20 cm 0.2 m 0.0002 km 7.874 in 0.65617 ft 0.21872 yd 0.00012427 mi 0.00010799 nmi
centimeters to inches
cmin
10.393701
20.787402
51.9685
103.93701
259.84252
5019.685
10039.3701

How the Unit Converter works

One centimeter is exactly 0.3937007874 inches. That is a definition rather than a measurement: the imperial and US customary units were fixed against metric ones by the 1959 international yard and pound agreement, so this factor does not drift and will not be revised.

Worked through: 25 cm x 0.393700787 = 9.84252 in.

Going the other way, one inch is 2.54 centimeters.

For mental arithmetic: Divide by 2.5 and take off 2%: 30 cm is 12 less a bit, so 11.8 inches.

The most searched conversion on the internet, and almost always about a body measurement or a screen. Clothing sizes, heights and televisions are quoted in centimeters in most of the world and inches in the US, so this is the pair that bridges a shopping decision more often than an engineering one.

Precision is worth matching to the input. A measurement given as 1 cm carries one or two significant figures, and reporting its conversion to six implies a precision the original never had.

Unit Converter FAQ

How many inches are in a centimeter?

0.39370079. That is exact by definition: the 1959 international yard and pound agreement fixed it, and it does not change.

What is 20 cm in inches?

7.87402 in. Multiply by 0.39370079: 25 cm x 0.393700787 = 9.84252 in.

How do I convert inches back to centimeters?

Divide by 0.39370079, or equivalently multiply by 2.54. One inch is 2.54 centimeters. The two factors are reciprocals, so you only need to remember one of them.

Is there a quick way to do this in my head?

Divide by 2.5 and take off 2%: 30 cm is 12 less a bit, so 11.8 inches. It is close enough for everyday use.

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