Opening tool…
Runs in your browser. Nothing you enter is uploaded to ALCO.
About this tool.
Convert between the units people actually need: meters and feet, kilograms and pounds, liters and gallons, Celsius and Fahrenheit, kilowatt hours and BTUs, bar and psi. Units are grouped by what they measure, so a conversion can never cross dimensions, and each result is shown alongside the same amount in every other unit of that group. The factors are the exact defined ones — an inch is exactly 25.4 mm — and both US and imperial fluid measures are listed separately because they are not the same size.
Using this tool.
Why are there two kinds of gallon and fluid ounce?
Because there are two systems still in use. A US gallon is 3.785 liters and an imperial gallon is 4.546, so a recipe or a fuel figure converted with the wrong one is out by a fifth. Both are listed with their system named.
Why does it refuse temperatures below absolute zero?
Because they do not exist. Anything below −273.15 °C is not a colder temperature, it is a typo or a unit mix-up, and returning a number for it would only hide the mistake.
How long is a month here?
The average length of a month in the Gregorian calendar, 30.44 days, which is the only sensible constant for a unit conversion. When you need the exact gap between two dates, use the date difference calculator instead.
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