Everyday & industry
Volume Converter
Convert liquid volume between litres, millilitres, US gallons, Imperial gallons, cups, fluid ounces, pints, quarts and other common units.
Enter a liquid volume, choose the source unit, and convert it instantly to another common metric, US customary or imperial unit.
US and Imperial volume units are not always the same size. This calculator treats them as separate units.
Results update as you edit. Calculations run locally in your browser; your inputs are not saved.
Choose your volume units.
Calculated locally · Volume Converter
Your Volume Conversion
The converted value represents the same liquid volume in another unit.
Result Detail
Conversion Breakdown
Source value × source-to-litres factor ÷ target-to-litres factor. Display rounding does not change the calculation.
About this calculator
US vs Imperial Volume Units
US customary and Imperial units share some names but are different sizes. These fixed references are separate, not calculated from your current inputs.
- 1 US gallon = 3.785411784 L.
- 1 Imperial gallon = 4.54609 L.
- 1 US fluid ounce = 29.5735295625 mL.
- 1 Imperial fluid ounce = 28.4130625 mL.
Quick Conversion References
Liquid-volume relationships for common metric, US customary and Imperial units.
- 1 L = 1000 mL.
- 1 US gallon ≈ 3.78541 L.
- 1 Imperial gallon = 4.54609 L.
- 1 US cup ≈ 236.588 mL.
- 1 US fluid ounce ≈ 29.5735 mL.
- 1 Imperial fluid ounce ≈ 28.4131 mL.
Liquid Volume and Precision
Conversions use the full-precision litre value internally. Rounded display values are not reused in calculations.
- Auto uses up to two decimal places for values of 1000 or more, four for values of at least 1, and six for values below 1. Unnecessary trailing zeros are removed.
- Use Decimal Places to choose 0–4 or 6 decimal places. Scientific notation is reserved for extremely small or large values.
- A US cup, pint, quart or gallon is distinct from its Imperial counterpart.
Frequently asked questions
How many litres are in a US gallon?
One US gallon is exactly 3.785411784 litres.
How many litres are in an Imperial gallon?
One Imperial gallon is exactly 4.54609 litres.
How many millilitres are in a US fluid ounce?
One US fluid ounce is 29.5735295625 millilitres.
How many millilitres are in an Imperial fluid ounce?
One Imperial fluid ounce is 28.4130625 millilitres.
How many US cups are in a litre?
One litre is approximately 4.22675284 US customary cups.
What is the difference between US and Imperial gallons?
One US gallon is 3.785411784 litres. One Imperial gallon is 4.54609 litres, so an Imperial gallon holds more.
Can I convert cups of flour to grams with this tool?
No. This tool converts volume to volume. Converting ingredients from volume to weight requires the ingredient’s density and belongs in a separate cooking or ingredient-conversion tool.
This tool converts liquid volume only. It does not convert ingredient weight to volume, apply density values or provide cooking, nutrition or hydration advice.