Cm to inches

Type a length in centimeters or in inches and pick the direction. The calculator divides or multiplies by 2.54 and leaves one number. 180 cm is 70.8661 in, not a ready 5 ft 11.

The cm and in pair. Threads and sheet: millimeters and inches. Height in meters: meters and feet.

Inputs

Result

Enter a value. The result shows up here.

How it works

The international inch is exactly 2.54 cm, because it is 25.4 mm. A 180 cm height is 70.8661 in. A 30 cm school ruler is 11.8110 in, not a clean 12. Ten centimeters is 3.9370 in. 1 in back is 2.5400 cm, not a 2.5 shortcut.

A US form asks for height in inches, while an ID lists centimeters. Type 180 and leave cm. A 50 cm waist is 19.6850 in. A US letter 8.5 in is 21.5900 cm. 67 in is 170.1800 cm, about 5 ft 7, but feet are not printed here. A 15.6 in laptop is a diagonal, 39.6240 cm, not the chassis width.

Pick the direction from the list: cm to inches or inches to cm. A comma and a period both work. Typed zero is allowed. A minus is rejected. Four decimals stay, because 1 cm is 0.3937 in and “0.4” already lies on a glasses frame. The header switch sets cm or inches on an empty field and does not overwrite a typed 180.

Millimeters are next door for a thread or sheet. 180 cm is not 1800 mm typed here. Height in meters and feet lives on a sibling card when someone gives 1.80 m instead of 180 cm.

The page does not print 5 ft 11 in. 180 cm is a little under 71 in. A tailor inch is not different here: we take 2.54 cm from 1959.

Do not mix 180 with 1800, and do not type a laptop diagonal as a desk width. One field, one length, one direction.

How to use

  1. Type a length, for example 180 for height or 15.6 from a label.
  2. Pick cm to inches or inches to cm.
  3. Click Calculate. 180 cm gives 70.8661 in. 15.6 cm gives 6.1417 in.
  4. You will not get 5 ft 11. Inches only, no feet.
  5. For a thread, open millimeters. For height in meters, open meters and feet.

Formula

in = cm / 2.54

cm = in × 2.54

The same 25.4 mm inch. This is not split into feet and leftover inches.

cm and in from the 2.54 factor

Here 180 cm is 70.8661 in. The calculator multiplies or divides by 2.54 and leaves one number, not a ready 5 ft 11.

cm
Centimeters of length. 180 / 2.54 = 70.8661 in. The same 25.4 mm inch, with no split into feet.
in
International inch. 70.8661 from 180 cm. The other way, in × 2.54 returns cm. This is not 5 ft 11.

Real-life examples

Example 1

180 cm -> 70.8661 in of height.

Example 2

1 in -> 2.5400 cm on the tape.

Example 3

10 cm -> 3.9370 in on the tape.

Example 4

30 cm -> 11.8110 in of school ruler.

Example 5

8.5 in -> 21.5900 cm of US letter.

Example 6

50 cm -> 19.6850 in of waist.

Example 7

67 in -> 170.1800 cm, about 5 ft 7.

Ways to use this converter

  • You convert height from centimeters when a US form asks for height in inches.
  • You check a waist from a cm tag against a size chart in inches.

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Frequently asked questions

Is 1 inch 2.54 cm here, or 2.5?

Exactly 2.54 cm. A 2.5 cm shortcut is too loose for height and for frames.

Will the page print 5 ft 11?

You get one number in inches or cm. 180 cm is 70.8661 in.

Can height be negative?

Zero cm is allowed. Compute a difference yourself and type a positive number.

How many inches is 180 cm, and is 30 cm 12 inches?

180 / 2.54 is 70.8661 in. 30 cm is 11.8110 in, not 12. Twelve inches are 30.48 cm.

How is this different from millimeters and inches?

Same family, different scale. Threads and sheet metal use mm. Height and waist usually use cm. Do not mix 180 with 1800.

How do I type a 15.6 in laptop diagonal?

Type 15.6 or 15,6 and leave inches. You get 39.6240 cm. That is the screen diagonal, not chassis width.

Is a 30 cm ruler exactly 12 inches?

30 cm is 11.8110 in. Twelve inches are 30.48 cm. A 30 cm school ruler is not a foot.

How many cm are 67 in and 8.5 in?

67 in is 170.1800 cm. An 8.5 in US letter is 21.5900 cm. A 50 cm waist is 19.6850 in.

Why four decimals on 180 cm?

180 cm is 70.8661 in. Rounding to 71 in is already more than 0.3 cm. That is too much on a glasses frame.

Is a tailor inch different?

Not on this page. We take 2.54 cm, the 1959 definition.

Knowledge sources

The converter multiplies your number by an SI factor. NIST SP 330 and BIPM define the units, not your reading.

Page updated in 2026.