Inches to Centimeters Converter (in to cm)
1 in = 2.54 cm exactly. Convert inches to centimeters for screen sizes, US paper, product dimensions and ruler fractions, with charts.
cm = in × 2.54
Inch (in): The inch is exactly 2.54 centimetres, a value fixed by the 1959 international yard and pound agreement. It is used in the US and UK for screen sizes, tools, pipes and body measurements.
Centimeter (cm): The centimetre is one hundredth of a metre (0.01 m). It is used for everyday measurements such as body height, clothing and paper sizes, and one inch is exactly 2.54 cm.
| Inch (in) | Centimeter (cm) |
|---|---|
| 1 | 2.54 |
| 5 | 12.7 |
| 10 | 25.4 |
| 25 | 63.5 |
| 50 | 127 |
| 100 | 254 |
Inch figures turn up wherever a US or older British specification meets a metric reader: the diagonal of a TV or phone screen, a US Letter page, a pipe or bolt size, a listing from an American store. Because the 1959 international yard and pound agreement set the inch at exactly 2.54 cm, multiplying by 2.54 gives an exact answer with no rounding hidden inside the factor.
The first chart includes ruler fractions you meet on a tape measure, such as an eighth, three-eighths and three-quarters of an inch, written as decimals, along with popular screen sizes. Screens are measured corner to corner, so a 55-inch television is 55 inches on the diagonal, not across its width.
How to use this tool
- Type a value in the Inch box to see it in centimeters, or type in the Centimeter box to convert the other way.
- Press ⇄ to swap the two units, or Load example for a typical value.
- Check the charts below for common values; for other units, open the Length converter.
Formula
cm = in × 2.54
in = cm ÷ 2.54
Both factors come from exact definitions: 1 centimeter = 0.393700787402 inches and 1 inch = 2.54 centimeters (shown to 12 significant digits).
Example
Two conversions worked with the same factors the converter uses:
27 in × 2.54 = 68.58 cm
40 cm × 0.393700787402 ≈ 15.748 in
Inch to Centimeter chart
Common values from inches to centimeters, rounded to four decimal places.
| Inch (in) | Centimeter (cm) |
|---|---|
| 0.125 | 0.3175 |
| 0.375 | 0.9525 |
| 0.75 | 1.905 |
| 1 | 2.54 |
| 1.5 | 3.81 |
| 2.5 | 6.35 |
| 3.5 | 8.89 |
| 6.1 | 15.494 |
| 7 | 17.78 |
| 8.5 | 21.59 |
| 9 | 22.86 |
| 11 | 27.94 |
| 13 | 33.02 |
| 14 | 35.56 |
| 16 | 40.64 |
| 17 | 43.18 |
| 21.5 | 54.61 |
| 27 | 68.58 |
| 32 | 81.28 |
| 34 | 86.36 |
| 40 | 101.6 |
| 43 | 109.22 |
| 50 | 127 |
| 55 | 139.7 |
| 65 | 165.1 |
| 75 | 190.5 |
| 85 | 215.9 |
Centimeter to Inch chart
The reverse direction for values people often look up.
| Centimeter (cm) | Inch (in) |
|---|---|
| 0.5 | 0.1969 |
| 1.5 | 0.5906 |
| 4 | 1.5748 |
| 7 | 2.7559 |
| 12 | 4.7244 |
| 18 | 7.0866 |
| 22 | 8.6614 |
| 28 | 11.0236 |
| 35 | 13.7795 |
| 45 | 17.7165 |
| 56 | 22.0472 |
| 64 | 25.1969 |
| 75 | 29.5276 |
| 95 | 37.4016 |
| 110 | 43.3071 |
| 140 | 55.1181 |
Common sizes given in inches
| Item | Inch (in) | Centimeter (cm) |
|---|---|---|
| US Letter paper, short side | 8.5 | 21.59 |
| US Letter paper, long side | 11 | 27.94 |
| US quarter coin, diameter | 0.955 | 2.4257 |
| Golf hole, diameter set by the Rules of Golf | 4.25 | 10.795 |
| Basketball rim, inside diameter | 18 | 45.72 |
| Dressed 2×4 lumber, wider face | 3.5 | 8.89 |
| Laptop screen, a common 15.6-inch diagonal | 15.6 | 39.624 |
| Bowling pin, regulation height | 15 | 38.1 |
Quick mental estimate
Multiply the inches by 10 and divide by 4: 12 in → 30 cm, while the exact answer is 30.48 cm. Dividing by 4 treats the factor as 2.5 instead of 2.54, so the quick figure is about 1.6% low; adding 4 mm for every 10 inches makes the result exact.
Use the converter or the charts when the exact figure matters.
The two units
Inch (in): The inch is exactly 2.54 centimetres, a value fixed by the 1959 international yard and pound agreement. It is used in the US and UK for screen sizes, tools, pipes and body measurements.
Centimeter (cm): The centimetre is one hundredth of a metre (0.01 m). It is used for everyday measurements such as body height, clothing and paper sizes, and one inch is exactly 2.54 cm.
Frequently asked questions
Why is an inch exactly 2.54 centimeters?
In 1959 the US, the UK, Canada, Australia, New Zealand and South Africa agreed on a common yard of exactly 0.9144 m. The inch is 1/36 of that yard, which works out to exactly 2.54 cm.
How do I convert a fraction of an inch to centimeters?
Turn the fraction into a decimal first, then multiply by 2.54: three-eighths of an inch (0.375 in) is 0.9525 cm. The fraction to decimal calculator helps with awkward fractions such as eleven-sixteenths.
How big is a 65-inch TV in centimeters?
The 65 inches is the diagonal, about 165 cm. For a 16:9 screen the picture itself is roughly 144 cm wide and 81 cm tall; the frame and stand add a little to both.
How precise is the result?
The converter uses the exact definitions above with browser floating-point arithmetic and shows up to 12 significant digits. The charts round to four decimal places for reading.
Sources
Last updated:
Page address with these inputs: https://kakao.mobile/tools/inch-to-centimeter-converter/
Cite or embed this tool
kakaoCalc. (2026, November 8). Inches to Centimeters Converter (in to cm). https://kakao.mobile/tools/inch-to-centimeter-converter/
“Inches to Centimeters Converter (in to cm).” kakaoCalc, 8 Nov. 2026, kakao.mobile/tools/inch-to-centimeter-converter/.
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