Free Unit Converter Online
Convert length, weight, area, volume, speed and data storage units instantly. Remembers your last used unit pair.
About the Unit Converter
This free online unit converter lets you convert between common measurement units across six categories: length, weight, area, volume, speed and data storage. All conversions happen instantly in your browser as you type — no button press needed. The last-used category and unit pair are saved so they're ready on your next visit.
How to Use the Unit Converter
Select a Category
Choose Length, Weight, Area, Volume, Speed or Data from the category tabs.
Pick Your Units
Select the source unit (From) and target unit (To) from the dropdowns.
Enter a Value
Type your value — the converted result appears instantly below as you type.
Supported Unit Categories
Length
Metre, kilometre, mile, foot, inch, yard, centimetre, millimetre, nautical mile.
Weight
Kilogram, gram, pound, ounce, tonne, milligram, stone.
Area
Square metre, square kilometre, square mile, square foot, acre, hectare.
Volume
Litre, millilitre, cubic metre, US gallon, pint, cup, fluid ounce, cubic foot.
Speed
m/s, km/h, mph, knots, ft/s.
Data
Byte, kilobyte, megabyte, gigabyte, terabyte, bit, kibibyte, mebibyte.