Free Unit Converter with Step-by-Step Solutions
Exact NIST and BIPM factors. Runs in your browser. No sign-up.
Unit converter
1 centimetre = 0.3937 inches
Default is 5 significant figures. “Search units as” decides what words like gallon, pint or cup mean when you type them. Shortcuts: Alt+S swap · Alt+C copy · Alt+L link · / search
- 1 cm = 0.3937 in
- 5 cm = 1.9685 in
- 10 cm = 3.937 in
- 25 cm = 9.8425 in
- Metresm
- Kilometreskm
- Centimetrescm
- Millimetresmm
- Micrometresµm
- Nanometresnm
- Inchesin
- Feetft
- Yardsyd
- Milesmi
- Nautical milesnmi
- Milsmil
- US survey feetft (US survey)
- Astronomical unitsau
- Light-yearsly
- ÅngströmsÅ
- Metres0.01m
- Kilometres0.00001km
- Centimetres1cm
- Millimetres10mm
- Micrometres10,000µm
- Nanometres10,000,000nm
- Inches0.3937in
- Feet0.032808ft
- Yards0.010936yd
- Miles0.0000062137mi
- Nautical miles0.0000053996nmi
- Mils393.7mil
- US survey feet0.032808ft (US survey)
- Astronomical unitsau
- Light-yearsly
- Ångströms100,000,000Å
Popular conversions
All converters- 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
Browse by category
Frequently asked questions
How do I use the converter?
Pick a group tab (Everyday, Engineering and so on), then a category such as Length or Pressure. Choose a unit in the From list and one in the To list, and type your value. The answer appears straight away, and the To list shows the value in every other unit too. You can also type a unit name like “psi” or a phrase like “150 lbs to kg” into the search box above the tabs.
How do I see the working?
Tap “Show steps” under the answer. It shows the conversion factor, 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 lists is labelled US or UK, and under Options you can choose what words like “gallon” mean when you type them in the search box.
Where do the conversion factors come from?
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.
Do you store my conversions?
Only on your own device. Recent conversions and favourites are saved in your browser’s local storage and never sent to a server. You can clear them at any time.