Volume Converter

Convert gallons, quarts, cups and fluid ounces to liters and milliliters, cubic feet and yards, UK (imperial) measures and barrels.

Decimals, fractions (3 1/2) and e-notation (1.5e6) all work.
Common Conversions
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Formula
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How to Convert Volume Units

The US gallon is defined as 231 cubic inches, which is exactly 3.785411784 liters. The rest of the US liquid measures divide it down: 4 quarts, 8 pints, 16 cups or 128 fluid ounces per gallon.

L = gal × 3.785411784   mL = fl oz × 29.5735295625

Worked Example

Common Conversions

FromEquals
1 gal3.785412 L
1 L0.2641721 gal
1 fl oz29.57353 mL
1 mL0.03381402 fl oz
1 cup236.5882 mL
1 qt0.9463529 L
1 ft³7.480519 gal
1 UK gal1.20095 gal

Unit Definitions

UnitEqualsExact?
Milliliters (mL)0.001 LExact
Liters (L)1 LExact
Cubic meters (m³)1,000 LExact
US teaspoons (tsp)0.004928921594 LExact
US tablespoons (tbsp)0.01478676478 LExact
US fluid ounces (fl oz)0.02957352956 LExact
US cups (cup)0.2365882365 LExact
US pints (pt)0.473176473 LExact
US quarts (qt)0.946352946 LExact
US gallons (gal)3.785411784 LExact
Cubic inches (in³)0.016387064 LExact
Cubic feet (ft³)28.31684659 LExact
Cubic yards (yd³)764.554858 LExact
UK fluid ounces (UK fl oz)0.0284130625 LExact
UK pints (UK pt)0.56826125 LExact
UK gallons (UK gal)4.54609 LExact
Oil barrels (42 gal) (bbl)158.9872949 LExact
Acre-feet (ac·ft)1,233,481.837999999989 LExact

Factors follow NIST Special Publication 811, Appendix B. "Exact" means the unit is defined as that value; results are rounded only for display.

Tips

UK (imperial) gallons are 4.54609 L, about 20% bigger than US gallons, but a UK fluid ounce is slightly smaller than a US one. Nutrition labels use a rounded 240 mL "legal" cup; this page uses the exact customary cup (236.59 mL).