Volume Converter
Convert litres, millilitres, Australian and US cups, fluid ounces, cubic metres and US or UK gallons instantly with exact factors.
Your results
Calculation breakdown
- Conversion
- Result = value × (from unit's litres) ÷ (to unit's litres)
Worked example
Converting 10 litres to US gallons gives approximately 2.64172 US gallons. A 1-cup measure in an American recipe is about 236.6 mL, slightly less than the 250 mL Australian metric cup.
Assumptions
- Distinguishes US gallons and cups from UK (imperial) gallons and the 250 mL Australian metric cup, which are all different sizes.
- Results are shown to six significant figures; very small results use scientific notation instead of rounding to zero.
How this calculator works
This calculator converts a volume value between metric units such as litres and millilitres and imperial or US customary units such as gallons, cups and fluid ounces. Litres are the standard Australian unit for fuel, drinks and cooking, while gallons and cups are common in American recipes and equipment specifications.
Australian, US and UK volume units are not the same
Australia uses litres and millilitres for fuel, drinks and cooking, and the Australian metric cup holds 250 mL. A US cup is about 236.6 mL, a US gallon is about 3.785 litres and a UK imperial gallon is about 4.546 litres, so choosing the correct country's unit matters.
Select the unit you are starting with and the unit you need. The converter changes the value into litres using exact factors and then into the target unit, keeping six significant figures so small amounts are not rounded down to zero.
- 1 Australian metric cup = 250 mL
- 1 US cup ≈ 236.6 mL
- 1 US gallon ≈ 3.785 L
- 1 UK gallon ≈ 4.546 L
- 1 cubic metre = 1,000 L
Recipes, fuel and water volumes
For overseas recipes, convert liquid measures by volume and weigh dry ingredients where possible, because flour and sugar vary with how firmly they are packed. The gap between US and Australian cups is small for one cup but adds up in larger batches.
American fuel figures are often quoted per US gallon, and water tanks or pools may be rated in gallons or cubic metres. Convert the volume here first, then use a fuel or pool calculator to estimate costs or filling time.
Frequently asked questions
Is a US gallon the same as a UK gallon?
No, a US gallon is about 3.785 litres while a UK (imperial) gallon is about 4.546 litres, so this calculator treats them separately.
What volume unit does Australia use for fuel?
Australia sells fuel by the litre, so this converter is handy for comparing to gallon-based fuel figures from other countries.
Is an Australian cup the same as a US cup?
No. An Australian metric cup is 250 mL, while a US cup is about 236.6 mL, so choose the cup type that matches the recipe's country of origin.
Content responsibility
Maintained by CalcAussie and last updated 15 October 2026. Checks applied: calculation method, worked examples, Australian terminology, material assumptions, official references where an external rule applies, and user-facing limitations.
Calculator results remain estimates based on the figures entered. Check material decisions against current official information and report a suspected error so it can be reproduced and corrected.