How to use the Volume Converter
- Type the amount, for example 2 for a 2-liter bottle.
- Choose the starting unit and the target unit. US and imperial (UK) measures appear in separate groups.
- Read the result and the matching one-unit factor.
- Browse the complete list of equivalents and click any value to copy it.
Features
- Separate US customary and imperial (UK) units
- Exact legal factors, e.g. 1 US gallon = 3.785411784 L
- Kitchen units: teaspoons, tablespoons, cups and fluid ounces
- Cubic inches, feet and yards, and 42-gallon oil barrels
- Every unit at once with one-click copy
- Clickable table of everyday conversions
The liter and its relatives
The liter is the volume of a cube 10 cm on each side, one cubic decimeter. Between 1901 and 1964 it was briefly defined as the volume of one kilogram of water, which turned out to be about 28 parts per million larger, so in 1964 it was tied back to exactly 1 dm³. A milliliter is therefore exactly one cubic centimeter, which is why engines and syringes are labeled in “cc”. One cubic meter holds 1,000 liters.
US gallons versus imperial gallons
American and British units share names but not sizes. The US gallon descends from the old English wine gallon of 231 cubic inches, which is exactly 3.785411784 liters. Britain replaced its assortment of gallons in 1824 with the imperial gallon, originally the volume of 10 pounds of water and now defined as exactly 4.54609 liters.
The smaller units are trickier. A US fluid ounce (29.57 mL) is larger than an imperial fluid ounce (28.41 mL), yet a US pint of 16 fluid ounces (473 mL) is smaller than an imperial pint of 20 fluid ounces (568 mL). Always check which system a recipe, fuel figure or product label uses.
Cubic units and barrels
Cubic feet describe refrigerators, shipping space and natural gas; cubic yards are the usual way to order concrete, soil and gravel in the US. Crude oil is priced per barrel of 42 US gallons, about 158.99 liters, a size inherited from the early Pennsylvania oil fields.
Worked examples
A 50-liter fuel tank: 50 ÷ 3.785411784 = 13.21 US gallons, but only 50 ÷ 4.54609 = 11.00 imperial gallons.
A 12 US fl oz can: 12 × 29.5735 = 354.9 mL, which is why cans are often labeled 355 mL.
A garden bed 3 m × 1 m × 0.3 m: 0.9 m³ = 900 liters = 1.18 cubic yards of soil.
Reference table
| Unit | Milliliters (exact) |
|---|---|
| US teaspoon | 4.92892159375 |
| US tablespoon | 14.78676478125 |
| US fluid ounce | 29.5735295625 |
| US cup | 236.5882365 |
| US pint | 473.176473 |
| Imperial pint | 568.26125 |
| US gallon | 3,785.411784 |
| Imperial gallon | 4,546.09 |
Cups are not one size
The US customary cup is 236.59 mL, US nutrition labels use a rounded 240 mL cup, and Australia, New Zealand and Canada commonly use a 250 mL metric cup. For baking, measuring by weight is far more reliable than by volume; the Cooking Converter turns cups of flour, sugar or butter into grams.
Frequently asked questions
How many liters are in a gallon?
A US gallon is exactly 3.785411784 liters. An imperial (UK) gallon is exactly 4.54609 liters, about 20% more.
How many milliliters are in a cup?
A US customary cup is about 236.6 mL, the cup on US nutrition labels is 240 mL, and a metric cup is 250 mL.
Is a cc the same as a milliliter?
Yes. One cubic centimeter (cc) is exactly one milliliter, because a liter is defined as one cubic decimeter.
Why is a UK pint bigger than a US pint?
A UK pint holds 20 imperial fluid ounces (568 mL) while a US pint holds 16 US fluid ounces (473 mL). The two countries standardized their units separately.
How many liters are in a cubic foot?
One cubic foot is exactly 28.316846592 liters, because a foot is exactly 0.3048 m and 0.3048³ m³ is 0.0283168 m³.