LengthWise

Centimeters to Inches Converter

Divide by 2.54 — and for heights, see the feet-and-inches equivalents in the table.

centimetres (cm)

inches (in)

centimetres → inches

30 cm = 11.81 in

Type in either box — the other updates to match.

centimetres to inches conversion table

Everyday lengths plus the adult height range (150–200 cm).

centimetres (cm)	inches (in)
1 cm	0.39 in
2 cm	0.79 in
5 cm	1.97 in
10 cm	3.94 in
15 cm	5.91 in
20 cm	7.87 in
25 cm	9.84 in
30 cm	11.81 in
40 cm	15.75 in
50 cm	19.69 in
60 cm	23.62 in
75 cm	29.53 in
100 cm	39.37 in
150 cm	59.06 in
160 cm	62.99 in
170 cm	66.93 in
180 cm	70.87 in
200 cm	78.74 in

What you entered

centimetres: 30 cm

1
Conversion factor
1 cm = 0.3937 in= × 0.3937
2
Multiply by the value
30 × 0.3937= 11.811 in

Result

inches: 11.81 in

30 cm equals 11.81 in, because one centimetre is 0.394 in.

Common measurements in centimetres and inches

Dividing by 2.54 converts centimetres to inches. These rows cover everyday objects and the adult height range.

What it is	cm	in
Credit card length	8.56	3.37
A4 paper width	21	8.27
A4 paper height	29.7	11.69
Standard desk height	75	29.53
Kitchen counter height	90	35.43
Adult female average height	162	63.78
Adult male average height	175	68.90
Standard doorway height	200	78.74

Height is the most common reason people convert centimetres: 175 cm is 68.90 inches, which is 5 feet 8.9 inches - remember to divide the inches by 12 and keep the remainder rather than reading 68.90 as feet. A rough mental conversion is to divide by 2.5 and subtract 2%, which puts 100 cm at about 39.2 inches against the true 39.37. The relationship is exact in the other direction, since an inch is defined as exactly 2.54 cm.

Converting centimetres to inches means dividing by 2.54, because one inch is defined as exactly 2.54 centimetres. That definition, agreed internationally in 1959, makes the conversion exact in both directions: there is no rounding built into the factor itself, only into however many decimal places you choose to display.

Most people arrive at this conversion for one of two reasons. The first is height. Metric countries record height in centimetres, while the United States and United Kingdom still speak in feet and inches, so a figure like 175 cm needs translating into something a US audience recognises — in that case about 68.9 inches, or 5 foot 9. The table on this page deliberately covers the 150 to 200 cm range for exactly this reason, so you can find a height without doing the arithmetic. The second reason is product dimensions: furniture, luggage, screens, and clothing are frequently listed in centimetres by international sellers and in inches by American ones.

For heights specifically, the two-step nature of the conversion trips people up. Dividing centimetres by 2.54 gives a decimal number of inches, but feet-and-inches notation needs that split into whole feet and a remainder. For 175 cm, 68.9 inches divides into 5 feet (60 inches) with 8.9 inches left over — so 5 foot 9 when rounded. The mistake to avoid is treating the decimal part as a fraction of a foot rather than a number of inches; 68.9 inches is not 68 feet 9 inches, and a decimal like 5.74 feet is not 5 foot 7.

When a measurement needs to be precise — a component that must fit, a frame that must hold a specific print — carry more decimal places through the calculation and round only at the end. Rounding to the nearest whole inch early can introduce an error of over a centimetre, which is easily enough to matter for a physical fit.

Heights need a two-step conversion

Dividing centimetres by 2.54 gives decimal inches, not feet and inches. 175 cm is 68.9 inches, which is 5 feet (60 inches) plus 8.9 inches — about 5 foot 9. Treating the decimal as a fraction of a foot is the classic error: 5.74 feet is not 5 foot 7.

Round at the end, not the start

Rounding to the nearest inch early can shift the result by more than a centimetre, which matters for anything that has to physically fit. Carry the decimals through your calculation and round only the final answer.

Frequently asked questions

How do I convert cm to inches?

Divide the centimetres by 2.54. So 30 cm ÷ 2.54 = 11.81 inches. The factor is exact because the inch is defined as exactly 2.54 cm, so the only approximation is your chosen number of decimal places.

What is 175 cm in feet and inches?

175 cm ÷ 2.54 = 68.9 inches. Sixty of those inches make 5 feet, leaving 8.9 inches — so roughly 5 foot 9. Convert to total inches first, then split into feet and a remainder.

What is 100 cm in inches?

Exactly 39.37 inches (to two decimals). One metre is a little over 39⅜ inches, which is why a metre and a yard — 36 inches — are close but not equal; a metre is about 9% longer.

Is 2.54 an approximation?

No. The inch has been defined as exactly 2.54 cm since the 1959 international agreement, so the factor carries no uncertainty. Any imprecision in a converted figure comes from rounding the display, not from the conversion itself.