Length converter
CM to Inches Converter
Convert centimeters to decimal inches, feet plus inches, and common inch fractions in one result. The calculation stays in your browser.
How to convert cm to inches
The international inch is defined as exactly 2.54 centimeters, so the conversion uses an exact constant before the displayed result is rounded.
inches = centimeters ÷ 2.54
centimeters = inches × 2.54
1 inch = 2.54 centimeters exactly
Example: 170 cm ÷ 2.54 = 66.929133… in. That is 5 ft 6.93 in, while the nearest 1/16-inch fraction is 66 15/16 in.
Where cm-to-inch conversion is useful
Centimeters are common in metric specifications, while U.S. listings and personal measurements often use inches.
Height and fit
Compare a height recorded in centimeters with a U.S. height listing in feet and inches without dropping the leftover inches.
Clothing and product sizing
Translate garment, screen, frame, and package dimensions before comparing a metric size chart with an inch-based listing.
Furniture and home measurements
Check whether a metric width or depth matches the inch measurements used for shelves, desks, and other household items.
Common cm to inches chart
The decimal-inch column is rounded to two places; the feet-and-inches column keeps two decimal places on the remaining inches.
| Centimeters (cm) | Inches (in) | Feet + inches |
|---|---|---|
| 1 | 0.39 | 0 ft 0.39 in |
| 2.54 | 1.00 | 0 ft 1.00 in |
| 5 | 1.97 | 0 ft 1.97 in |
| 10 | 3.94 | 0 ft 3.94 in |
| 15 | 5.91 | 0 ft 5.91 in |
| 20 | 7.87 | 0 ft 7.87 in |
| 25 | 9.84 | 0 ft 9.84 in |
| 30 | 11.81 | 0 ft 11.81 in |
| 50 | 19.69 | 1 ft 7.69 in |
| 75 | 29.53 | 2 ft 5.53 in |
| 100 | 39.37 | 3 ft 3.37 in |
| 150 | 59.06 | 4 ft 11.06 in |
| 160 | 62.99 | 5 ft 2.99 in |
| 170 | 66.93 | 5 ft 6.93 in |
| 180 | 70.87 | 5 ft 10.87 in |
Precision, feet-plus-inches, and fraction results
The precision menu changes only the displayed rounding. It does not change the exact 2.54 cm-per-inch constant used for the calculation.
Feet plus inches is split after converting the full length to inches. If rounding makes the remainder 12.00 inches, the converter carries it into the next whole foot instead of showing an invalid 12-inch remainder.
The 1/8, 1/16, 1/32, and 1/64 cards round the same unrounded inch value independently, so you can compare common ruler and shop resolutions without changing a setting.
For manufacturing tolerances or a purchase that must fit a tight opening, keep the original measurement and match the precision required by the drawing or seller rather than treating a rounded display as a new exact value.
Sources and method
The unit constants come from the primary standards below. ToolNeko applies those constants in a browser-only calculation, then rounds only the displayed result.
- NIST — SI Units: Length States that the standard inch is exactly 25.4 mm, which is exactly 2.54 cm.
- NIST Guide to the SI, Appendix B — Conversion Factors Provides U.S. customary and SI conversion-factor guidance and rounding references.
Frequently asked questions
How do I convert cm to inches?
Divide the number of centimeters by 2.54. For example, 30 cm ÷ 2.54 = 11.8110… inches.
How many inches are in 1 cm?
One centimeter is approximately 0.3937007874 inches. The decimal repeats because the exact definition runs in the other direction: 1 inch equals exactly 2.54 cm.
What is 170 cm in feet and inches?
170 cm is about 66.9291 inches, or 5 feet 6.93 inches. Rounded to the nearest whole inch, that is 5 feet 7 inches.
Why is decimal inches different from feet and inches?
Decimal inches expresses the entire length in inches. Feet and inches groups every 12 inches into one foot and shows only the remainder as inches; both formats describe the same length.
Does changing the decimal setting change the conversion?
No. It changes the displayed rounding only. The converter always calculates with the exact relationship of 1 inch to 2.54 centimeters.