Unit converter

Type an amount with its unit and read the answer at once. Or choose a family below and type in any of its units: every other unit follows. Sixteen families, from length and cups to time, data rates and blood tests.

Free. No ads, no paid extras, no tracking, no sign-up. Nothing you type here is sent anywhere.

Convert

Amount and unit

For example 350 F, 2 cups, 11 st 4 lb, 1 cup flour in g, 3 GiB in GB, 120 mg/dL glucose.

Answer

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Every unit of a family, together. Choose a family to start from its example; type in any field and the rest follow, and the line above with them. The ring beside a unit makes it the answer.

The link holds the line after the # sign, a part browsers never send to a server, with its meaning and its answer spelt out, so it opens the same conversion anywhere. Copy link also puts it in the address bar, so it stays in this browser’s history.

Nothing is sent and nothing is stored. Every number is worked out in your browser, and the page makes no request after it has loaded. On zeromile.tools it is served with connect-src 'none', so the browser itself refuses any connection its script might try to open.

How this converts

Typing: A number, then its unit: 5 ft 10 in, 350 F, 2 US cups, 60 mph. Add to, in or = and a unit to choose the answer’s unit: 3 GiB in GB, or press the ring beside any unit below. A dot marks decimals, and so does a comma (1.5 and 1,5 are the same), except a comma before exactly three digits, which groups thousands as the answers do: 1,500 g is fifteen hundred grams, like 1 500 g. The line under the answer always says which number it read. Fractions work: 1 1/2 cups, 1 ½ cups, ½ tsp. A number alone keeps the unit in use.
Exact or rounded: The sums are done on exact fractions, never on rounded numbers. A result that ends within 15 digits is shown whole after an = sign: 1 in = 2.54 cm. Any other is shown after ≈ and rounded: to 6 significant digits (1 kg ≈ 2.20462 lb), cooking weights to 3, blood tests as a laboratory reports them (to 4 significant digits in a unit a laboratory does not report for that substance), and an answer in stone and pounds or feet and inches to a tenth of a pound or an inch (70 kg ≈ 11 st 0.3 lb). A result with more whole digits than that keeps every one of them (10,000 km ≈ 32,808,399 ft), and none is written in powers of ten. The line under the answer says which rule it used.
Words with two meanings: Cup, pint, gallon, fluid ounce, spoon, ton, ounce, degrees, mpg, calories, mb, gr and nm each name more than one unit. The line takes one meaning and shows the others beside the answer, with their own answers; one click changes it. In a recipe, T is a tablespoon, and c and t before an ingredient are a cup and a teaspoon (2 c flour); alone they stay Celsius and a tonne, with the kitchen meaning offered. From 300 up, degrees alone is an oven in Fahrenheit.
Your region: The first meaning of a word and some answers follow your browser’s language. In the United Kingdom a cup is the 250 mL metric cup and spoons are metric (15 and 5 mL); a pint, a gallon, a fluid ounce, a ton and mpg are UK ones; millilitres and litres are answered in UK fluid ounces, pints or gallons, a body weight in stone and pounds, and L/100 km and km/L in UK mpg. In the United States cups, spoons, pints, gallons, fluid ounces, tons and mpg are US ones, and L/100 km and km/L are answered in US mpg. In Australia, New Zealand and Canada a cup is 250 mL, spoons are metric (but an Australian tablespoon is 20 mL), a pint, a gallon and mpg are UK ones and a ton is a tonne; a fluid ounce is a UK one in Australia and New Zealand and a US one in Canada; litres are answered in UK pints or gallons (millilitres in UK fluid ounces, except in Canada) and L/100 km in UK mpg. Elsewhere cups, spoons, fluid ounces, gallons and mpg are US ones, a pint is a UK pint and a ton a tonne; L/100 km is answered in km/L, and kW and W in metric horsepower. Everywhere but the United States, degrees alone are Celsius below 300. In cooking, a weight is answered in the region’s cup. Nothing is stored: Change chooses another region for as long as the page is open.
Not a factor: Temperature has an offset, fuel economy is an inverse (L/100 km is about 235.2 divided by US mpg, so 0 has no answer), a slope in percent is a tangent, and cups to grams go through the ingredient. Each family page says how.
Not here: Currencies: their rates change by the minute, so the page would have to ask a server, and this page asks nothing. Time zones, clothing, shoe and pipe sizes: they follow tables and rules, not a formula.