Volume Converter

It opens set to convert a US gallon into litres, and everything updates as you type.

1. Enter the amount in Value. A recipe quantity like 0.75 or a tank size like 60 both work.
2. Under From, choose the unit on your recipe, fuel receipt or product label. Check the wording carefully, because several entries carry a country tag such as Cup (US) or Gallon (UK).
3. Under To, choose the unit you want. The answer appears at once, with a note such as 1 US gal = 3.7854 L.
4. Use Swap units to check the same amount in the opposite direction.
5. Look through the In every unit list to see your amount as spoonfuls, cups, litres and cubic measures side by side. It is a quick way to find a size that suits a measuring jug you actually own.

American recipes are built on a neat ladder of US customary units, and the converter follows it exactly. A US cup is 236.588 ml, and everything else hangs from it.

So one tablespoon is three teaspoons, and a cup holds 16 tablespoons or 48 teaspoons. A recipe asking for 3 tablespoons equals 1.5 fluid ounces. Half a litre, 500 ml, is about 16.9 US fluid ounces, and 250 ml is 1.0567 US cups. Because the metric cup used in Australia, Canada and many British recipes is a round 250 ml, it is roughly 5 percent larger than the US cup, and the converter does not model it. For small bakes that gap can matter, so use the same cup throughout a recipe.

The word gallon names two different volumes. A US gallon is 3.7854 litres. An imperial or UK gallon is 4.54609 litres, which is about 20 percent more, or 1.2009 US gallons. Both are listed separately here and labelled in the dropdowns, so choose carefully.

• 10 US gallons = 37.85 L, while 10 UK gallons = 45.46 L
• A 60 L fuel tank holds 15.85 US gallons or 13.20 UK gallons
• 1 cubic foot = 28.317 L, and 1 cubic metre = 1,000 L = 264.17 US gallons
• 1 litre = 2.1134 US pints = 0.2642 US gallons

This matters when comparing fuel economy. A car advertised at 40 miles per UK gallon manages roughly 33 miles per US gallon, so check which gallon a figure uses before judging a vehicle. The UK pint and UK fluid ounce are not in the list, only the US versions and the UK gallon.

One firm limit: this is a volume converter, not a weight converter. A cup of flour, a cup of honey and a cup of water all fill the same space but weigh very different amounts, so a recipe given in grams cannot be turned into cups here. Use the weight converter for mass, the temperature converter for oven settings and the length converter for container dimensions. For a restaurant bill rather than a recipe, try the tip calculator.

Most volume mistakes come from the wrong variant, not from the arithmetic. Before relying on a number, confirm four things: which gallon the source means, whether a fluid ounce is US or imperial, whether the recipe uses US cups or a 250 ml metric cup, and whether the amount is level or heaped.

Rounding shortcuts are tempting but cost accuracy. Treating a cup as 240 ml overstates it by about 1.4 percent, which is harmless in soup and noticeable in a delicate cake. For liquids, read the jug at eye level on a flat surface. The converter shows up to four decimal places between 1 and 1,000, so you can round the answer to whatever your measuring equipment can actually resolve.

For larger containers, remember that listed capacity and usable capacity differ. A tank or tub is rarely filled to the brim, so leave room for expansion and splashing, and treat the converted volume as the nominal figure.