Free converter

cm to Inches Converter

Convert centimetres to inches or inches to centimetres using the exact international inch definition, with feet-and-inches height results.

Conversions run in your browser. Entered and converted numbers are not placed in the URL or analytics.

How to use this tool

Enter a finite value, choose centimetres or inches, and swap the direction when needed. Centimetre-to-inch results also show a precise feet-and-inches breakdown and a separately labelled nearest-inch height.

Transparent method

Formula and method

Inches = centimetres ÷ 2.54. Centimetres = inches × 2.54.

Worked examples

1 centimetre ÷ 2.54 = 0.393700787402 inches.
2.54 centimetres ÷ 2.54 = exactly 1 inch.
170 centimetres = 66.9291338583 inches, or approximately 5 feet 6.93 inches; rounded to the nearest whole inch, that is about 5 feet 7 inches.
72 inches × 2.54 = 182.88 centimetres.

Assumptions and limits

One international inch equals exactly 2.54 centimetres.
The engine keeps full internal precision; the main display uses up to 12 significant digits.
Feet-and-inches output is derived from the converted total inches, with 12 inches in one foot.
The precise feet-and-inches result uses up to two decimal places for the remaining inches.
The optional human-height result is clearly labelled as rounded to the nearest whole inch.
Zero, decimals and negative values are supported mathematically; negative physical length may not be meaningful in every use case.

How to convert cm to inches

Divide the centimetre value by 2.54. The converter routes the value through the shared CorelyUp measurement engine, so the focused page and the general Unit Converter use the same definition and precision policy.

cm to inches formula

Inches = centimetres ÷ 2.54. For example, 170 cm ÷ 2.54 = 66.9291338583 inches with the page's display precision.

How to convert inches to cm

Multiply the inch value by 2.54. One inch is 2.54 cm, 12 inches is 30.48 cm, 24 inches is 60.96 cm, and 72 inches is 182.88 cm.

Why 1 inch equals exactly 2.54 cm

The international inch is defined as exactly 0.0254 metre, which is exactly 2.54 centimetres. The factor is a definition rather than an estimated approximation.

cm to feet and inches

The calculator first converts centimetres to total inches. It then divides the absolute total by 12: complete groups of 12 become feet and the remainder becomes inches. A negative sign is preserved when a negative input is used.

For 170 cm, the exact conversion is 66.9291338583 inches. That separates into approximately 5 ft 6.93 in. The optional conventional height is independently labelled as about 5 ft 7 in because it rounds to the nearest whole inch.

Common height conversions

The compact height table provides frequently checked centimetre values without generating hundreds of thin rows. Every value is calculated at build time with the same shared engine used by the interactive converter.

Metric and inch measurement

Centimetres are metric units based on the metre. Inches and feet are commonly used in US customary and British Imperial contexts, although the international inch has the same exact metric definition in each system.

Convert other length and measurement units with the Unit Converter

Rounding and common mistakes

Do not multiply centimetres by 2.54 when converting to inches; divide by 2.54. Multiply by 2.54 only when converting inches to centimetres.

The main conversion retains full internal precision and formats the display without intermediate rounding. Feet-and-inches and nearest-inch height are convenience formats, so they remain visibly separate from the precise inch result.

Common cm to inches conversions

A curated set of practical centimetre values converted by the shared measurement engine.

Common centimetre values in inches and feet plus inches
Centimetres	Inches	Feet + inches
1	0.3937008	0 ft 0.39 in
2.54	1	0 ft 1 in
10	3.937008	0 ft 3.94 in
20	7.874016	0 ft 7.87 in
30	11.81102	0 ft 11.81 in
50	19.68504	1 ft 7.69 in
100	39.37008	3 ft 3.37 in
150	59.05512	4 ft 11.06 in
160	62.99213	5 ft 2.99 in
165	64.96063	5 ft 4.96 in
170	66.92913	5 ft 6.93 in
175	68.89764	5 ft 8.9 in
180	70.86614	5 ft 10.87 in
185	72.83465	6 ft 0.83 in
190	74.80315	6 ft 2.8 in
200	78.74016	6 ft 6.74 in

Common height conversion table

Frequently checked human-height values, shown as precise inches and feet plus remaining inches.

Common heights from centimetres to inches and feet plus inches
Centimetres	Inches	Feet + inches
150	59.05512	4 ft 11.06 in
155	61.02362	5 ft 1.02 in
160	62.99213	5 ft 2.99 in
165	64.96063	5 ft 4.96 in
170	66.92913	5 ft 6.93 in
175	68.89764	5 ft 8.9 in
180	70.86614	5 ft 10.87 in
185	72.83465	6 ft 0.83 in
190	74.80315	6 ft 2.8 in
195	76.77165	6 ft 4.77 in
200	78.74016	6 ft 6.74 in

Sources

NIST Guide to the SI — conversion factors

Frequently asked questions

How many inches are in 1 cm?

One centimetre is approximately 0.393700787402 international inches.

How do I convert cm to inches?

Divide the centimetre value by exactly 2.54. For example, 25.4 cm divided by 2.54 is 10 inches.

How do I convert inches to cm?

Multiply the inch value by exactly 2.54. For example, 12 inches multiplied by 2.54 is 30.48 cm.

Is 1 inch exactly 2.54 cm?

Yes. The international inch is defined as exactly 0.0254 metre, so one inch is exactly 2.54 centimetres.

How tall is 170 cm in feet and inches?

170 cm is 66.9291338583 inches, approximately 5 ft 6.93 in, or about 5 ft 7 in when rounded to the nearest whole inch.

How many cm are in 6 feet?

Six feet is 72 inches. Multiplying 72 by exactly 2.54 gives 182.88 centimetres.

Why do cm-to-inch results have decimals?

Most centimetre values are not exact whole multiples of 2.54, so their equivalent in inches includes a decimal remainder.

Does the calculator round the result?

The engine does not round intermediate values. The main result uses up to 12 significant digits; feet-and-inches uses up to two decimal places, and the nearest-inch height is separately labelled as rounded.

Can I convert a negative length?

The calculation supports it mathematically, although a negative physical length may not be meaningful for your use case.