How to convert centimetres to inches
To convert a length in centimetres to inches, divide it by 2.54. This works because the inch is defined as exactly 2.54 centimetres — a fixed legal definition agreed internationally in 1959, not a rounded approximation. So the conversion is precise, and the converter above updates instantly as you type in either direction.
For example, 10 cm ÷ 2.54 = 3.937 inches. One centimetre is about 0.3937 inches, and — going the other way — one inch is 2.54 cm. If you prefer a rough mental estimate, multiply centimetres by 0.4 (10 cm ≈ 4 in); it is close enough for a quick check but the calculator gives the exact figure.
Where the cm-to-inches conversion comes up
Most of the world measures length in centimetres, while the United States and, for some everyday things, the United Kingdom still use inches. That mismatch is why this is one of the most-searched conversions online. You will typically need it when:
- Height: a passport, gym app or medical form lists your height in cm, but you want it in feet and inches (or vice versa).
- Screens: TVs, monitors, laptops and phones are advertised by their diagonal in inches, while packaging dimensions are often printed in cm.
- Buying furniture and appliances: checking whether a 60 cm-wide fridge or a 140 cm desk will fit a space you measured with an inch tape.
- Clothing and sewing: waist, inseam and fabric measurements switch between the two systems depending on the brand or pattern.
- Photo printing and paper: a 10×15 cm print is the metric name for the familiar 4×6 inch photo; A4 paper is 21.0 cm (8.27 in) wide.
- DIY and airline luggage: matching a cm measurement to an inch-based cut list, or an inch-based bag limit to your cm suitcase.
Centimetres and inches: what each unit is
The centimetre is a metric unit equal to one-hundredth of a metre, part of the SI system used by most countries for science and daily life. The inch is an imperial and US customary unit; twelve inches make a foot and thirty-six make a yard. Since the 1959 international yard and pound agreement, one inch has been fixed at 2.54 cm exactly, which is what makes converting between them clean and reliable.
Centimetres to Inches conversion table
| Centimetres | Inches |
|---|
Common heights in centimetres, inches and feet
Because “what is my height in feet and inches” is the single most common reason people convert cm, here is a quick reference for typical adult heights:
| Centimetres | Inches | Feet & inches |
|---|---|---|
| 150 cm | 59.1 in | 4 ft 11 in |
| 160 cm | 63.0 in | 5 ft 3 in |
| 165 cm | 65.0 in | 5 ft 5 in |
| 170 cm | 66.9 in | 5 ft 7 in |
| 175 cm | 68.9 in | 5 ft 9 in |
| 180 cm | 70.9 in | 5 ft 11 in |
| 185 cm | 72.8 in | 6 ft 1 in |
| 190 cm | 74.8 in | 6 ft 3 in |
Worked examples
Convert 30 cm to inches
30 ÷ 2.54 = 11.81 inches — roughly the length of a standard 12-inch ruler.
Convert 100 cm to inches
100 ÷ 2.54 = 39.37 inches. One metre is a little over 39 inches, or about 3 feet 3 inches.
Convert 170 cm to feet and inches
170 ÷ 2.54 = 66.93 inches. Divide by 12: that is 5 feet with 6.9 inches left over, so about 5 ft 7 in.
Frequently asked questions
One centimetre equals 0.3937 inches. To go the other way, one inch equals 2.54 cm.
Yes. The inch is defined as exactly 2.54 cm, so the conversion factor is exact, not an approximation. Any rounding you see is only in how many decimal places are shown.
Convert to inches first (divide by 2.54), then divide that by 12 for the feet and keep the remainder as inches. For example, 170 cm = 66.93 in = 5 ft 6.9 in.
TV sizes are the screen’s diagonal in inches. Multiply by 2.54 to get centimetres: a 55-inch TV is about 140 cm across the diagonal, a 65-inch is about 165 cm. Remember the physical width of the set is less than the diagonal.
The metric system (centimetres) was designed in France in the 1790s to be decimal and universal, and most countries adopted it. The inch descends from older body-based measures still used in the US and parts of the UK. Both are now defined against the same metric standard, which is why they convert exactly.