Length Converter
Length measures distance along a single dimension. The SI base unit is the meter, defined from the speed of light. Everyday conversions cross between the metric system (meters, centimeters, kilometers) and US/Imperial units (inches, feet, yards, miles).
About length conversion
Length conversion is commonly needed when measuring height, screen sizes, travel distances, fabric, and construction dimensions. Metric and Imperial length units are both in daily use, so quick conversion is often needed when following instructions from another country.
Popular conversions
All length units
| Unit | Symbol | System |
|---|---|---|
| Meter | m | SI |
| Kilometer | km | SI |
| Centimeter | cm | SI |
| Millimeter | mm | SI |
| Micrometer | µm | SI |
| Nanometer | nm | SI |
| Mile | mi | Imperial |
| Yard | yd | Imperial |
| Foot | ft | Imperial |
| Inch | in | Imperial |
| Nautical Mile | nmi | Other |
Frequently asked questions
What is the base unit for length?
Length conversions on this site are calculated against the meter (m).
Which length units can I convert?
You can convert between 11 units, including meter, kilometer, centimeter, millimeter, and more.
Where is length conversion useful?
It is commonly needed when measuring height, screen sizes, travel distances, fabric, and construction dimensions.
Does this converter mix measurement systems?
The converter supports SI, Imperial, Other units and keeps their exact definitions separate so results stay accurate.