Centimetres to inches
Multiply centimetres by 0.393701 to get inches.
15 cm = 5.9055 in
How to convert centimetres to inches
The inch is exactly 2.54 centimetres (0.0254 m), by the 1959 international agreement. The centimetre is one hundredth of a metre (10⁻² m).
Worked example — 15 cm: 15 × 0.393701 = 5.9055 in.
Centimetres to inches table
| Centimetres | Inches |
|---|---|
| 1 cm | 0.393701 in |
| 2 cm | 0.787402 in |
| 5 cm | 1.9685 in |
| 10 cm | 3.937 in |
| 15 cm | 5.9055 in |
| 20 cm | 7.874 in |
| 30 cm | 11.811 in |
| 50 cm | 19.685 in |
| 100 cm | 39.3701 in |
Reverse and related
About centimetres and inches
Centimetre (cm)
1 cm = 0.393701 inDefinition. One hundredth of a metre (10⁻² m)
History and origin
The centimetre is one hundredth of a metre, part of the decimal metric system introduced in France in the 1790s. It was the base length of the older centimetre-gram-second system before the metre-kilogram-second system prevailed.
Current use
Centimetres are the everyday metric unit for body height, paper and screen sizes, and clothing measurements.
Source: BIPM, The International System of Units (SI), 9th ed. (2019)
Inch (in)
1 in = 2.54 cmDefinition. Exactly 2.54 centimetres (0.0254 m), by the 1959 international agreement
History and origin
The inch takes its name from the Latin uncia, a twelfth part, and has always been one twelfth of a foot. The 1959 agreement fixed it at exactly 2.54 centimetres.
Current use
Inches are used for screen and TV sizes worldwide, and in the United States for height, lumber and hardware.
Source: International Yard and Pound Agreement (1959); NIST Handbook 44, App. C
Where people use this
Centimetres: height, paper and screen sizes, clothing measurements. Inches: screen sizes, height, lumber and hardware. A4 paper is 21 cm wide, about 8.27 inches.
Every value is carried to full double precision; the display is rounded.
Sources: International Yard and Pound Agreement (1959); NIST Handbook 44, App. C; BIPM, The International System of Units (SI), 9th ed. (2019).
Questions people ask
How many inches is 1 cm?
One centimetre is about 0.3937 inches. To convert cm to inches, divide by 2.54, so 30 cm is about 11.8 inches.
How many inches is 30 cm?
30 cm is about 11.8 inches (30 ÷ 2.54). A 30 cm ruler is just under 12 inches, which is one foot.
Is 2.5 cm an inch?
Almost. One inch is exactly 2.54 cm, so 2.5 cm is a hair under an inch.
How many inches is 100 cm?
100 cm, which is one metre, is about 39.37 inches, a little over a yard.
How big is A4 paper in inches?
A4 paper is 21 cm wide and 29.7 cm tall, about 8.27 by 11.7 inches.