Free Unit Converter with Step-by-Step Solutions
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Unit converter
Convert from
- Centimetrescm
- Inchesin
- Metresm
- Kilometreskm
- Millimetresmm
- Micrometresµm
- Nanometresnm
- Feetft
- Yardsyd
- Milesmi
- Nautical milesnmi
- Milsmil
- US survey feetft (US survey)
- Astronomical unitsau
- Light-yearsly
- ÅngströmsÅ
1 centimetre = 0.3937 inches
Default is 5 significant figures. “Units typed as” decides what words like gallon, pint or cup mean when you type them. Scientific input such as 1e15 or 2.5e-3 works in the value box; type unit names or a whole conversion in the unit picker’s search.
- 1 cm = 0.3937 in
- 5 cm = 1.9685 in
- 10 cm = 3.937 in
- 25 cm = 9.8425 in
Shortcuts: / value box · S swap · Esc close the picker · Alt+C copy · Alt+L link · Alt+F favourite
How it’s calculated
1 cm ≈ 0.39370079 in · 1 in = 2.54 cm (exact)
in = cm ÷ 2.54
- Divide the value in centimetres by 2.54.
- Equivalently, multiply by 0.3937007874.
- 1 cm = 0.3937007874 in · 1 in = 2.54 cm
Step by step
Find the conversion factor
By definition 1 cm = 0.01 m and 1 in = 0.0254 m, so 1 in = 2.54 cm. Source: BIPM SI Brochure (9th ed.); NIST SP 811 / Handbook 44.
Multiply by the factor written as a fraction
Put cm in the denominator so it cancels, leaving in.
Calculate (unrounded)
Round the answer
Rounded to 5 significant figures.
Answer: 0.3937 in
Formula: in = cm ÷ 2.54. Factors last reviewed 2026-10-27.
Popular conversions
- Pounds to kilograms1 lb = 0.45359 kg
- Degrees Celsius to degrees Fahrenheit1 °C = 33.8 °F
- Centimetres to inches1 cm = 0.3937 in
- Pounds per square inch to bar1 psi = 0.068948 bar
- Kilometres to miles1 km = 0.62137 mi
- Newton metres to pound-force feet1 N·m = 0.73756 lbf·ft
- Feet to metres1 ft = 0.3048 m
- BTU per hour to watts1 BTU/h = 0.29307 W
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Frequently asked questions
How do I use Unitglide?
Type a number in the left box and the answer appears in the right box straight away. Tap the unit name under either box to pick another unit or switch category. The search at the top of that list also takes a whole conversion, such as “150 lb to kg” or “psi”. The round button in the middle swaps the two units.
How do I see the working?
Open “How it’s calculated” below the Unitglide converter. It follows the units and number on screen and shows the conversion factor, the formula, how the units cancel and how the result was rounded. It is closed by default so the page stays simple.
Are US and UK units different?
Some are. US and imperial gallons, pints, cups, fluid ounces and tons have different sizes. Every unit in the unit picker is labelled US or UK, and under Options › Precision you can choose what words like “gallon” mean when you type them in the value box.
Where does Unitglide get its conversion factors?
From exact definitions published by NIST (SP 811 and Handbook 44) and the BIPM SI Brochure. Conversions run entirely in your browser, so they work offline once the page has loaded.
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