This switches a length between metric units like meters and kilometers and imperial units like feet and miles, plus centimeters, millimeters, yards, and inches. It's for the moment a measurement shows up in the wrong system for whatever you're doing, whether that's reading a recipe, checking furniture dimensions, or converting a race distance.
How to use it
- Type the value you want to convert.
- Choose the unit you're converting from.
- Choose the unit you want it in.
- Read the converted value underneath.
- Swap the two units if you need the conversion going the other way.
When it helps
- Converting furniture dimensions between inches and centimeters before ordering online.
- Working out how far a race distance in kilometers is in miles.
- Converting a recipe measurement from one country's usual unit to another.
- Checking whether a package fits a size limit given in a different unit.
- Converting a construction measurement between metric and imperial.
Good to know
- Double check which unit you actually need. Feet and yards get mixed up easily when reading specs quickly.
- For precise engineering work, round only at the very end, so small errors don't stack up.
- One meter is a little over 3.28 feet, a useful figure for a rough sanity check.
- For shipping or travel measurements, round to a sensible number of decimal places for the context. Three decimal places is rarely necessary for everyday use.
- If you're converting for a DIY project, round to the nearest practical measurement your tape measure or ruler actually shows, rather than keeping every decimal place.
Sanity checks
A quick way to catch a slip is to compare against a known length: one inch is 2.54 centimetres, a mile is about 1.609 kilometres, and a metre is a little over three feet.
Questions
How accurate are these conversions?
They use standard, internationally recognized factors, like exactly 2.54 centimeters per inch, so the result is accurate to the precision shown.
Can I convert between two imperial units, like feet and yards?
Yes, both dropdowns list every supported unit, so you can convert metric to metric, imperial to imperial, or across the two.
Why do some results show a lot of decimal places?
Because the conversion factors aren't always round numbers. The extra decimals keep the result accurate instead of rounding it arbitrarily.
Which unit should I use for something very small, like electronics?
Millimeters are usually most practical for small measurements, since centimeters or meters would need awkward decimals for anything much smaller than a few centimeters.
Is a nautical mile the same as a regular mile?
No, a nautical mile is a different, slightly longer unit used mainly in maritime and aviation. This converter's mile option is the standard statute mile used for everyday distance.
Are metric units used consistently worldwide, unlike imperial ones?
Mostly yes, metric units are standardized internationally, while imperial units have occasionally had small regional variations historically, though the versions used today are generally consistent.