📏 cm to inches Converter
By Shihab Mia · Updated 2026-07-12
10 cm = 3.937 in
That is 0 ft 3.94 in
To convert centimeters to inches, divide the centimeter value by 2.54, because 1 inch is defined as exactly 2.54 cm. For example, 10 cm divided by 2.54 equals 3.937 inches. This converter works both ways instantly: type a value in either the centimeter or the inch field and the other updates as you type, and it also breaks the result down into feet and inches.
What is the cm to inches Converter?
The centimeter is a metric unit equal to one hundredth of a meter, the base unit of length in the International System of Units (SI). The inch is an imperial and US customary unit. Since 1959 the inch has had a single agreed definition tied to the metric system: one inch is exactly 2.54 centimeters. That definition is what makes conversion clean and exact rather than an approximation.
Because the factor is exact, converting is simple arithmetic. To go from centimeters to inches you divide by 2.54, and to go from inches to centimeters you multiply by 2.54. There is no rounding built into the factor itself, so the only rounding that appears is whatever you choose to apply to the final answer for readability.
The reverse direction matters just as often as the forward one. A width printed in inches on US packaging, a screen size, or a paper size in inches can all be turned into centimeters by multiplying by 2.54. This tool keeps both fields live, so you never have to remember which way the factor points: type into whichever unit you already have and read the other.
Precision matters most when a small error compounds. Converting a single measurement for a rough idea, a few decimal places is plenty. But when you convert many segments and add them, or you are cutting material to size, rounding the factor early (for example using 2.5 instead of 2.54) introduces a real error. Keep the full 2.54 factor and round only the final displayed number.
When to use it
- Reading a height given in centimeters and expressing it in feet and inches, for example a 170 cm height as 5 ft 6.9 in.
- Converting a product dimension listed in cm on an overseas listing into inches before buying, so it fits your space.
- Turning a sewing or craft measurement from a metric pattern into inches for a tape measure marked in inches.
- Checking a screen, frame, or paper size quoted in inches against a metric ruler by converting to centimeters.
How to use the cm to inches Converter
- Type the value you already have into its field, centimeters on the left or inches on the right.
- Read the converted value in the other field, it updates the moment you type.
- Check the feet and inches line below for a height friendly breakdown.
- Use a preset button for a common value, or press Clear to start over.
Formula & method
Worked examples
Convert 10 cm to inches.
- Start with the value in centimeters: 10 cm
- Divide by the exact factor 2.54: 10 / 2.54
- 10 / 2.54 = 3.937 inches
Result: 10 cm = 3.937 in
Convert 170 cm to inches, then to feet and inches.
- Divide the centimeters by 2.54: 170 / 2.54 = 66.929 in
- Split off whole feet: floor(66.929 / 12) = 5 feet
- Find the leftover inches: 66.929 - (5 x 12) = 6.929 in
- Round for display: about 6.9 in
Result: 170 cm approx 66.93 in, which is 5 ft 6.9 in
cm to inches conversion chart for common values (1 in = 2.54 cm)
| Centimeters (cm) | Inches (in) | Feet and inches |
|---|---|---|
| 1 | 0.3937 | 0 ft 0.39 in |
| 2 | 0.7874 | 0 ft 0.79 in |
| 5 | 1.9685 | 0 ft 1.97 in |
| 10 | 3.9370 | 0 ft 3.94 in |
| 15 | 5.9055 | 0 ft 5.91 in |
| 20 | 7.8740 | 0 ft 7.87 in |
| 25 | 9.8425 | 0 ft 9.84 in |
| 30 | 11.8110 | 0 ft 11.81 in |
| 50 | 19.6850 | 1 ft 7.69 in |
| 100 | 39.3701 | 3 ft 3.37 in |
| 170 | 66.9291 | 5 ft 6.93 in |
inches to cm quick reference (multiply inches by 2.54)
| Inches (in) | Centimeters (cm) |
|---|---|
| 1 | 2.54 |
| 2 | 5.08 |
| 6 | 15.24 |
| 12 | 30.48 |
| 24 | 60.96 |
| 36 | 91.44 |
Common mistakes to avoid
- Rounding the 2.54 factor too early. Using 2.5 instead of the exact 2.54 looks close but is off by about 1.6 percent. On 100 cm that is roughly 0.6 inch of error. Keep the full 2.54 factor and only round the final answer.
- Converting in the wrong direction. To get inches you divide cm by 2.54, not multiply. Multiplying centimeters by 2.54 gives a much larger, wrong number. Remember: cm are smaller units than inches, so the inch count is always the smaller figure.
- Reading the decimal inches as feet and inches. 66.93 inches is not 66 feet 93 inches. To get feet and inches, divide the inch total by 12 for whole feet, then keep the remainder as inches. 66.93 in is 5 ft 6.93 in.
- Assuming the factor is only approximate. Since 1959 the inch has been defined as exactly 2.54 cm, so there is no measurement uncertainty in the factor itself. Any imprecision in your result comes only from how far you round, not from the conversion.
Glossary
- Centimeter (cm)
- A metric length unit equal to one hundredth of a meter, the SI base unit of length.
- Inch (in)
- An imperial and US customary length unit defined as exactly 2.54 centimeters.
- Foot (ft)
- An imperial length unit equal to 12 inches, or 30.48 centimeters.
- Conversion factor
- The fixed number you multiply or divide by to change units. Here it is exactly 2.54 cm per inch.
- Metric system
- The decimal measurement system built on units like the meter and centimeter, used in most of the world.
- Imperial units
- A system of units including inches, feet, and miles, still common in the United States and United Kingdom.
Frequently asked questions
How do I convert cm to inches?
Divide the number of centimeters by 2.54, since 1 inch equals exactly 2.54 cm. For example, 10 cm / 2.54 = 3.937 inches. To go back, multiply inches by 2.54 to get centimeters.
How many inches is 10 cm?
10 cm is 3.937 inches. You get this by dividing 10 by 2.54. Rounded to two decimals it is about 3.94 inches, which is just under 4 inches.
What is 170 cm in feet and inches?
170 cm is about 66.93 inches, which is 5 feet 6.9 inches. Divide 170 by 2.54 to get inches, then divide that by 12 for the feet and keep the remainder as inches.
Is 1 inch exactly 2.54 cm?
Yes. Since the international agreement of 1959, one inch is defined as exactly 2.54 centimeters. This is an exact definition, not a rounded approximation, so conversions are precise.
How do I convert inches to cm?
Multiply the number of inches by 2.54. For example, 12 inches x 2.54 = 30.48 cm, which is one foot. Type into the inch field of this tool and the centimeter value appears instantly.
How many cm is 1 inch?
One inch is exactly 2.54 centimeters. So 2 inches is 5.08 cm, 6 inches is 15.24 cm, and 12 inches (one foot) is 30.48 cm.