Metric and US volume units in one place
Volume measures how much space something takes up, or how much a container holds. Liquids are usually measured in milliliters and liters, while larger quantities use cubic meters. One liter equals 1,000 milliliters, and one cubic meter equals 1,000 liters.
The US customary system uses fluid ounces, cups, quarts and gallons, and these do not match the metric units neatly. A US gallon is about 3.785 liters, a quart is a quarter of a gallon, and a cup is a measuring unit with several slightly different definitions around the world.
This tool converts everything through liters. Your input is multiplied by the source unit's size in liters, then divided by the target unit's size, so you can go directly between any two supported units.
When volume conversions come up
Cooking is the everyday case. A recipe from another country may list milliliters when your measuring cups are marked in cups and fluid ounces. Fuel economy, aquarium sizing, paint coverage and water tank capacity all involve similar switches between liters and gallons.
Travel is another one. Fuel prices and tank sizes are shown in liters or gallons depending on the country, and converting lets you compare costs on equal terms. Medicine and nutrition labels may also use milliliters or fluid ounces.
If you work with shipping or storage, cubic meters are the standard for container capacity, while liters describe the content. Having them side by side avoids mistakes when estimating how much liquid fits.
How to convert volume with this tool
- Enter the amount in the number box under From. It starts at 1.
- Choose your starting unit from the From drop-down: Milliliters, Liters, Cubic Meters, Gallons, Quarts, Cups or Fluid Ounces.
- Choose the unit you want from the To drop-down, which offers the same seven units.
- Read the converted value in the To box. It updates immediately as you edit anything.
The tool opens on Milliliters to Liters. Results are rounded to six decimal places. Everything is calculated in your browser, and your numbers are never sent to a server.
Factors used and a note about cups
The factors, in liters, are: milliliter 0.001, cubic meter 1000, gallon 3.78541, quart 0.946353, cup 0.24 and fluid ounce 0.0295735. The gallon, quart and fluid ounce values match the US customary units, not the larger imperial (UK) ones, so a UK recipe or fuel figure in imperial gallons will not match.
The cup is the one to watch. This tool treats one cup as 0.24 liters, which is 240 milliliters, the metric cup used on many nutrition labels. A traditional US cup is slightly smaller, at about 236.6 milliliters. For ordinary cooking the difference is small, but it adds up in large batches or baking where proportions matter.
Worked checks: 2 gallons is 7.57082 liters, 2 cups is 480 milliliters, and 1 liter is about 4.166667 cups. To convert an ingredient by weight instead, use the Weight Converter, since volume and weight depend on the ingredient.