Metric, US and UK volume units
Metric volumes are based on the liter, which is the volume of a cube 10 cm on each side. A milliliter is a thousandth of a liter and a cubic meter is 1,000 liters.
The US and the UK use measures with the same names but different sizes. The US gallon is 231 cubic inches (3.785 l), the UK gallon is 4.54609 l. Both split into 4 quarts and 8 pints, but a US pint has 16 fluid ounces and a UK pint has 20, and the fluid ounces differ slightly too.
- 1 US cup is 8 US fluid ounces, or about 236.6 ml. Australia, Canada and New Zealand often use a metric cup of 250 ml.
- 1 US tablespoon is half a fluid ounce, or about 14.8 ml, and holds 3 teaspoons.
- 1 US teaspoon is about 4.93 ml.
Recipes that list flour or sugar in cups measure by volume. To get grams for a specific ingredient, use the Cups to Grams converter.
Common volume conversions
| From | Equals |
|---|---|
| 1 US gallon | 3.785411784 liters |
| 1 liter | 0.2641720524 US gallons |
| 1 UK gallon | 4.54609 liters |
| 1 US quart | 0.946352946 liters |
| 1 US pint | 473.176473 milliliters |
| 1 UK pint | 568.26125 milliliters |
| 1 US cup | 236.5882365 milliliters |
| 1 US fluid ounce | 29.57352956 milliliters |
| 1 US tablespoon | 14.78676478 milliliters |
| 1 US teaspoon | 4.928921594 milliliters |
| 1 cubic foot | 28.31684659 liters |
US cups to milliliters chart
| US cups (cup) | Milliliters (ml) |
|---|---|
| 0.25 | 59.15 |
| 0.5 | 118.3 |
| 0.75 | 177.4 |
| 1 | 236.6 |
| 1.5 | 354.9 |
| 2 | 473.2 |
| 3 | 709.8 |
| 4 | 946.4 |
Liters to US gallons chart
| Liters (l) | US gallons (gal) |
|---|---|
| 1 | 0.2642 |
| 2 | 0.5283 |
| 5 | 1.321 |
| 10 | 2.642 |
| 20 | 5.283 |
| 40 | 10.57 |
| 50 | 13.21 |
| 60 | 15.85 |
| 100 | 26.42 |
Where the conversions come up
Cooking first: a recipe calls for 2 cups of stock, your measuring jug is in milliliters, and the answer is 473 ml, or 500 if you use a metric cup. Tablespoons and teaspoons trip people up because the UK and Australian tablespoon are not the same size as the US one. Then there is fuel: miles per gallon in the US, miles per imperial gallon in the UK, liters per 100 km everywhere else, and the two gallons differ by 20 percent. Aquariums, paddling pools and water bottles come labeled in whichever unit the maker chose.
Shortcuts: liters to US gallons is divide by 3.8, liters to UK gallons divide by 4.5. A US cup is just under 240 ml, a US fluid ounce just under 30 ml, and a US pint is about half a liter.
How to use it
- 1Pick the two units. US and UK gallons, pints and fluid ounces are listed separately, so check the label before you choose.
- 2Enter the amount on whichever side you know. The other side follows, and swap turns the pair around.
- 3The list under the result shows the same amount in cups, tablespoons, teaspoons and every other unit. Tap one to convert into it, or copy the result or a link.
Frequently asked questions
How many milliliters are in a cup?
A US cup is about 236.6 ml. A metric cup, used in Australia, Canada and New Zealand, is 250 ml. Nutrition labels in the US round a cup to 240 ml.
Why are US and UK gallons different?
The US kept the old English wine gallon of 231 cubic inches, while the UK redefined its gallon in 1824. A UK gallon is about 20 percent larger than a US gallon.
How many fluid ounces are in a liter?
About 33.81 US fluid ounces or 35.20 UK fluid ounces.
How do I convert cups of flour to grams?
Cups measure volume, grams measure weight, so the answer depends on the ingredient. Use the Cups to Grams converter, which knows the density of common baking ingredients.
How many tablespoons are in a cup?
16 US tablespoons, or 48 teaspoons. A UK tablespoon is 15 ml and an Australian one 20 ml, so recipes from those countries come out slightly differently.