To convert centimeters to inches, divide by 2.54 (or multiply by about 0.3937). 30 cm is 11.81 inches, and a 175 cm person is 68.9 inches tall, or about 5 ft 8.9 in.
Most of the world measures height, furniture and product dimensions in centimeters. This page shows the result in decimal inches and, for heights, in feet and inches.
How to use the cm to inches converter
- Type the value in centimeters into the box. Decimals are fine.
- The result in inches updates as you type, along with the working.
- Need the other way? Switch the direction menu, or open the inches to cm converter.
Formula
The factor 2.54 is exact. Since the 1959 international yard and pound agreement, one inch has been defined as exactly 25.4 millimeters, so no rounding is involved in either direction.
Worked example
Convert a height of 175 cm to feet and inches.
- 175 ÷ 2.54 = 68.8976 in.
- 68.8976 ÷ 12 = 5 feet, remainder 8.8976 in.
- Result: 68.9 in, or 5 ft 8.9 in (usually written 5′9″ after rounding).
Centimeters to inches chart
Common values, rounded to 4 decimal places.
| Centimeters (cm) | Inches (in) | ft + in |
|---|---|---|
| 1 cm | 0.3937 in | 0 ft 0.4 in |
| 2 cm | 0.7874 in | 0 ft 0.8 in |
| 5 cm | 1.9685 in | 0 ft 2 in |
| 10 cm | 3.937 in | 0 ft 3.9 in |
| 15 cm | 5.9055 in | 0 ft 5.9 in |
| 20 cm | 7.874 in | 0 ft 7.9 in |
| 25 cm | 9.8425 in | 0 ft 9.8 in |
| 30 cm | 11.811 in | 0 ft 11.8 in |
| 40 cm | 15.748 in | 1 ft 3.7 in |
| 50 cm | 19.685 in | 1 ft 7.7 in |
| 60 cm | 23.622 in | 1 ft 11.6 in |
| 75 cm | 29.5276 in | 2 ft 5.5 in |
| 100 cm | 39.3701 in | 3 ft 3.4 in |
| 150 cm | 59.0551 in | 4 ft 11.1 in |
| 160 cm | 62.9921 in | 5 ft 3 in |
| 170 cm | 66.9291 in | 5 ft 6.9 in |
| 180 cm | 70.8661 in | 5 ft 10.9 in |
| 190 cm | 74.8031 in | 6 ft 2.8 in |
Where centimeters show up
- Height and body measurements: passports, medical records and sizing charts outside the US use cm.
- Online shopping: furniture, bags and luggage from overseas sellers are listed in cm. A 55 × 40 × 20 cm carry-on is 21.65 × 15.75 × 7.87 in.
- Bikes: road-bike frames are sized in cm (a 56 cm frame is about 22 in).
- Rulers: a standard 30 cm school ruler is 11.81 in, a little shorter than a foot.
Quick mental math
Multiply by 4 and divide by 10 (that is, × 0.4), then take off about 1.6%. For 50 cm: 50 × 0.4 = 20, minus 0.3 = 19.7 in (exact: 19.685).
Related conversions
Going the other way: inches to cm converter. Related pages: feet to inches converter, inches to feet converter, mm to inches converter. For other units in the same family, use the full length converter.
Caveats and assumptions
- Results show up to 10 significant digits; the chart is rounded for reading. Keep full precision for engineering, medical or legal work.
Frequently asked questions
How many inches is 1 cm?
About 0.393701 inches, a little under 4/10 of an inch.
What is 180 cm in feet and inches?
180 ÷ 2.54 = 70.87 in = 5 ft 10.87 in, usually rounded to 5′11″.
Is 30 cm equal to 12 inches?
Close, but no. 30 cm is 11.81 in, and 12 in is 30.48 cm.
How do I convert cm to feet?
Divide by 30.48. For example, 160 cm ÷ 30.48 = 5.25 ft, which is 5 ft 3 in.
Sources
- NIST — SI Units: Length (1959 definition of the inch) — 1 in = 25.4 mm exactly
- NIST SP 811 Appendix B.9 — Conversion factors — inch to centimeter
This calculator gives estimates for planning and education. Check measurements, local codes, supplier specs and your school's official policy before relying on a result. See our disclaimer and how we build and check calculators.