Volume Converter
A volume converter changes a liquid or space measurement from one unit to another, such as liters to gallons or cups to milliliters. This tool separates US customary and imperial (UK) units, which differ in size, and uses exact definitions: 1 US gallon = 3.785411784 liters and 1 imperial gallon = 4.54609 liters.
Free, no signup. Runs entirely in your browser; files and text are not uploaded.
How to use the Volume Converter
- Type the amount in the Value box.
- Pick the unit you have in From, for example US cups.
- Pick the unit you need in To, for example milliliters.
- Read or copy the result, and check the table for every other unit.
Features
- Metric: liters, milliliters, cubic meters and cubic centimeters
- US customary: gallons, quarts, pints, cups, fluid ounces, tablespoons, teaspoons, cubic feet and cubic inches
- Imperial (UK) gallons, quarts, pints and fluid ounces, grouped separately
- Exact factors derived from the US gallon (231 in³) and imperial gallon
- All-units table, presets, precision control and copy buttons
Frequently asked questions
How many liters are in a gallon?
A US gallon is exactly 3.785411784 liters. An imperial (UK) gallon is larger, at exactly 4.54609 liters.
How many milliliters are in a cup?
A US customary cup is 1/16 of a US gallon, about 236.59 mL. Many recipes round this to 240 mL, and a metric cup is 250 mL.
Is a US fluid ounce the same as a UK fluid ounce?
No. A US fluid ounce is about 29.57 mL and an imperial fluid ounce is about 28.41 mL. There are 128 US fl oz in a US gallon and 160 imperial fl oz in an imperial gallon.
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Built and reviewed by Naqash Thaheem, Technical Project Manager. Last reviewed 2026-09-24.