Length Converter
Convert between length and distance units — meters, feet, inches, miles, kilometers, yards, centimeters, nanometers, and more.
About this calculator
The unit-length page converts a distance into thirteen units at once, from nanometres and micrometres for engineering and science to nautical miles, light years and astronomical units for navigation and space. Type a value, pick its unit, and a grid of results appears.
Very large and very small results switch to scientific notation so they stay readable. The default starts at 1 foot, which is exactly 0.3048 metres, 30.48 centimetres and 12 inches.
How to use it
- Enter the Value.
- Choose the unit in From.
- Read the grid of conversions.
How it works
Conversions go through metres. 1 inch = 2.54 cm exactly, 1 foot = 0.3048 m exactly, 1 yard = 0.9144 m, 1 mile = 1,609.344 m and 1 nautical mile = 1,852 m. To convert, multiply by the factor of the starting unit and divide by the factor of the target unit: value × from ÷ to.
Worked example
1 foot in other units
| Metres | 0.3048 |
| Centimetres | 30.48 |
| Millimetres | 304.8 |
| Inches | 12 |
| Yards | 0.3333333 |
| Miles | 0.0001893939 |
Tips and common mistakes
- Remember 1 inch = 2.54 cm exactly. Many other factors derive from it.
- For heights, convert feet and inches to total inches first, then multiply by 2.54.
- Do not confuse a statute mile (1.609 km) with a nautical mile (1.852 km).
- Keep extra decimals during multi-step calculations and round at the end.
- Check the unit list twice. Millimetre and micrometre are easy to mix up on small values.
- Use micrometres and nanometres for lab and chip-size work.
Frequently asked questions
How many centimetres are in an inch?
Exactly 2.54 centimetres.
How many feet are in a metre?
About 3.28084 feet.
How many kilometres are in a mile?
1.609344 kilometres.
What is a nautical mile?
1,852 metres, used at sea and in aviation. It equals one minute of latitude.
What is a light year?
The distance light travels in a year, about 9.46 trillion kilometres.
How do I convert feet and inches to centimetres?
Multiply feet by 30.48 and inches by 2.54, then add the two results.
What is an astronomical unit?
About 149.6 million kilometres, the average distance from Earth to the Sun.