How to use the length converter
- Type a value in either box. Decimals with a comma or a point both work, and feet take 5'7".
- Choose the units on each side, or press the arrows to swap them.
- The table below shows the value in every unit at once. Click a row to convert to that unit.
About length units
Metric lengths step by powers of ten from the meter: 1 km is 1,000 m, 1 m is 100 cm and 1 cm is 10 mm. US and imperial lengths use their own steps: 12 inches to a foot, 3 feet to a yard and 1,760 yards to a mile.
One exact definition ties the two systems together. Since 1959 the inch has been exactly 2.54 cm, which makes the foot exactly 0.3048 m, the yard 0.9144 m and the mile 1,609.344 m, so conversions between them have no rounding error.
Two units catch people out. The nautical mile, used at sea and in the air, is exactly 1,852 m, about 15% longer than a land mile. And a mil in US engineering is a thousandth of an inch (0.0254 mm), not a millimeter.
Popular length conversions
- Centimeters to inches
- Inches to centimeters
- Meters to feet
- Feet to meters
- Kilometers to miles
- Miles to kilometers
- Inches to feet
- Feet to inches
- Millimeters to inches
- Inches to millimeters
- Feet to centimeters
- Centimeters to feet
- Yards to meters
- Meters to yards
- Miles to feet
- Inches to meters
- Meters to inches
- Feet to miles
- Yards to feet
- Feet to yards
- Miles to meters
- Meters to miles
- Nautical miles to kilometers
- Kilometers to nautical miles
- Centimeters to meters
- Meters to centimeters
- Millimeters to centimeters
- Centimeters to millimeters
- Kilometers to meters
- Meters to kilometers
- Millimeters to feet
- Micrometers (microns) to millimeters
- Nanometers to meters
- Light-years to kilometers
Length units
| Unit | Symbol | Definition |
|---|---|---|
| Nanometers | nm | 1 nm = 1 × 10⁻⁹ m |
| Micrometers | µm | 1 µm = 0.000001 m |
| Millimeters | mm | 1 mm = 0.001 m |
| Centimeters | cm | 1 cm = 0.01 m |
| Decimeters | dm | 1 dm = 0.1 m |
| Meters | m | The base unit |
| Kilometers | km | 1 km = 1,000 m |
| Inches | in | 1 in = 0.0254 m |
| Feet | ft | 1 ft = 0.3048 m |
| Yards | yd | 1 yd = 0.9144 m |
| Miles | mi | 1 mi = 1,609.344 m |
| Nautical miles | nmi | 1 nmi = 1,852 m |
| Thou | thou | 1 thou = 0.0000254 m |
| Furlongs | fur | 1 fur = 201.168 m |
| Light-years | ly | 1 ly = 9,460,730,472,580,800 m |
Converting something else? The unit converter covers every kind of unit in one place.