Volume Converter
Convert units of volume and capacity — liters, gallons, cups, pints, fluid ounces and more.
1 gal = 3.7854118 L
Popular Volume Conversions
- Milliliter to Liter
- Cubic Meter to Liter
- Cubic Centimeter to Liter
- Cubic Inch to Liter
- Cubic Foot to Liter
- US Gallon to Liter
- Imperial Gallon to Liter
- US Quart to Liter
- US Pint to Liter
- US Cup to Liter
- US Fluid Ounce to Liter
- Tablespoon to Liter
- Teaspoon to Liter
- Oil Barrel to Liter
- US Gallon to Milliliter
- US Gallon to Cubic Meter
- US Gallon to Cubic Centimeter
- US Gallon to Cubic Inch
- US Gallon to Cubic Foot
- US Gallon to Imperial Gallon
- US Gallon to US Quart
- US Gallon to US Pint
- US Gallon to US Cup
- US Gallon to US Fluid Ounce
- US Gallon to Tablespoon
- US Gallon to Teaspoon
- US Gallon to Oil Barrel
About volume units
Volume measures the three-dimensional space that a substance occupies. The liter is the everyday metric unit — exactly one cubic decimeter — and is used for liquids in nearly every country. For cooking, smaller units like milliliters, teaspoons, tablespoons, and cups are standard. Industrially, volume is measured in cubic meters or barrels. The US and Imperial systems both use gallons, pints, and fluid ounces, but the numbers are different: a US gallon is about 3.785 liters, an Imperial gallon is about 4.546 liters, and a US cup is exactly 240 mL while British recipes typically use 250 mL.
History & origin
The liter was defined in 1795 as part of the original metric system, initially as the volume of 1 kilogram of water at maximum density. The Imperial gallon was fixed in Britain in 1824 as the volume of exactly 10 pounds of water at 62°F. The US gallon descends from the old English wine gallon, which is why it is smaller than the Imperial gallon. Oil barrels — each holding exactly 42 US gallons (about 159 liters) — became standardised in the Pennsylvania oil fields of the 1860s and remain the global benchmark for crude oil trading.
Tips
The single biggest pitfall in volume conversion is assuming a recipe's 'gallon' or 'pint' is the same unit worldwide — it is not. A US pint is 473 mL; a British pint is 568 mL, roughly 20% larger. This matters for brewing, baking, and any recipe crossing the Atlantic. Similarly, a US fluid ounce (29.57 mL) differs from an Imperial fluid ounce (28.41 mL), so large volumes accumulate meaningful error if you treat them as equal.
Common questions
- What is the difference between a US gallon and an Imperial gallon?
- A US gallon is exactly 3.785411784 liters. An Imperial gallon is exactly 4.54609 liters — about 20% larger. Both contain 8 pints, but the pints themselves are different sizes. Always check which gallon a recipe, fuel spec, or tank capacity refers to.
- How many milliliters are in a US cup?
- A US cup is exactly 236.5882… mL, commonly rounded to 240 mL in recipes. An Australian and Canadian cup is 250 mL. A UK recipe rarely specifies cups at all, preferring grams for dry ingredients and milliliters for liquids.
- How many teaspoons are in a tablespoon?
- In both the US and metric cooking systems, 1 tablespoon = 3 teaspoons. A US tablespoon is about 14.79 mL; a metric tablespoon is exactly 15 mL. The difference is small enough to ignore in most recipes.