About the Length Converter
Distances turn up in engineering drawings, running logs, shipping manifests and astronomy, so a length converter has to cover a very wide range. This one spans thirteen units from nanometres to light years, including the imperial set of inch, foot, yard and mile, plus the nautical mile used in aviation and shipping.
All the imperial factors come from the 1959 international agreement, where the inch is exactly 0.0254 metres. That makes a mile exactly 1609.344 metres, so a marathon of 42.195 kilometres works out at 26.2187581 miles. The nautical mile is fixed at exactly 1852 metres by definition, not one sixtieth of a degree of latitude as the old rule of thumb suggests.
Enter one distance per line and the whole column converts together, which suits a list of measurements pulled out of a spreadsheet. The formula line tells you the multiplier being applied so you can reuse it in code, and the table underneath gives the round numbers people usually need. For surfaces rather than distances, open the Area Converter.
How to use
- Paste one length value per line.
- Pick the From and To units.
- Set Rounding if you want a fixed number of decimals.
- Copy the converted values or the reference table.
Common questions
- How many feet are in a metre?
- A metre is 3.280839895 feet. The reverse is exact: one foot is 0.3048 metres.
- What is the difference between a mile and a nautical mile?
- A statute mile is 1609.344 metres and a nautical mile is 1852 metres, so the nautical mile is about 15 percent longer.
- Does it handle very small units?
- Yes. Nanometres and micrometres are included, which covers wavelengths and semiconductor process sizes.
- Can I paste values that already carry a unit, such as 5 km?
- Yes. Trailing unit text is ignored and the number is converted using the units picked in the dropdowns.