CM to inches converter

inches = cm ÷ 2.54, or equivalently inches = cm × 0.393701.

The 2.54 factor is exact: since the 1959 international yard and pound agreement, one inch is defined as exactly 25.4 millimeters. The decimal 0.393701 is rounded, so dividing by 2.54 is the more precise method.

Example: 30 cm ÷ 2.54 = 11.811 in, which is 11 13/16 in to the nearest sixteenth.

US tape measures and rulers are marked in fractions of an inch, usually sixteenths, so a decimal like 11.811 isn't something you can find on the tape. The converter rounds the decimal part to the nearest fraction and simplifies it:

Centimeters	Decimal inches	Nearest 1/16	Nearest 1/64
2.5 cm	0.984 in	1 in	63/64 in
10 cm	3.937 in	3 15/16 in	3 15/16 in
30 cm	11.811 in	11 13/16 in	11 13/16 in
100 cm	39.370 in	39 3/8 in	39 3/8 in

For woodworking or sewing, 1/16 is usually plenty; machinists and engineers often prefer decimals.

Heights in the US and UK are usually given in feet and inches. Divide the inches by 12 for the feet and keep the remainder as inches:

Height (cm)	Inches	Feet and inches
152 cm	59.84 in	4′ 11 13/16″
160 cm	62.99 in	5′ 3″
170 cm	66.93 in	5′ 6 15/16″
180 cm	70.87 in	5′ 10 7/8″

So 170 cm is just under 5 feet 7 inches; to the nearest 1/64 it is 5′ 6 59/64″. The height converter does the same in both directions.

cm	inches
1 cm	0.3937 in
5 cm	1.9685 in
10 cm	3.9370 in
20 cm	7.8740 in
25 cm	9.8425 in
50 cm	19.6850 in
75 cm	29.5276 in
100 cm	39.3701 in

A meter (100 cm) is a little over 39 inches, about 3 inches longer than a yard.

• Divide by 2.5 for a fast mental estimate: 30 cm ÷ 2.5 = 12, close to the true 11.8.
• 10 cm is about 4 inches (3.94 in).
• A 30 cm school ruler is just under a foot (11.81 in), because a foot is 30.48 cm.

For anything you'll cut, sew or order, use the exact result. The value you type is saved in the page link, so the Share button sends the exact conversion.

To go the other way, use the inches to cm converter, which also accepts fractions such as 5 3/8. Common heights and lengths have their own pages, for example 170 cm, 180 cm and 30 cm.