Volume Converter
The Volume Converter instantly converts between metric and US customary volume units, including milliliters, liters, cubic meters, cubic feet, gallons, quarts, cups, and fluid ounces. The US customary units here nest by powers of two rather than powers of ten — 2 cups per pint, 2 pints per quart, 4 quarts per gallon — so converting among them is exact integer arithmetic, while bridging to the metric side always routes through the single defined constant of 1 US gallon = 3.78541 liters. Cubic feet and cubic meters relate the same way area units do: the conversion factor is the linear foot-to-meter factor cubed (0.3048³ = 0.028316846592 m³), not a separately chosen number.
How This Tool Works
Enter a value and choose your source and target volume units for an instant conversion.
Formula & Method
All units convert through liters as a common base, e.g., 1 US gallon = 3.78541 liters.
Example Calculation
2 US gallons converts to liters using the defined constant 1 US gallon = 3.78541 L: 2 × 3.78541 = 7.57082 L. The same 2 gallons converts to cups using the exact US customary relationship of 16 cups per gallon: 2 × 16 = 32 cups. A 750 mL wine bottle converts to US fluid ounces by first noting 1 fl oz = 0.0295735 L (3.78541 ÷ 128): 0.75 L ÷ 0.0295735 ≈ 25.36 fl oz.
Frequently Asked Questions
How many liters are in a gallon?+
One US gallon equals approximately 3.785 liters. Note that a UK (imperial) gallon is larger, at about 4.546 liters.
How many cups are in a liter?+
One liter equals approximately 4.23 US cups.
Does this use US or imperial gallons?+
This converter uses US customary units (US gallons, quarts, cups, fluid ounces) throughout.
Why is a US gallon smaller than a UK (imperial) gallon?+
The two were standardized from different historical references: the US gallon (3.78541 L) comes from the old English wine gallon of 231 cubic inches, while the imperial gallon (4.54609 L) was redefined in 1824 as the volume of 10 pounds of water. The imperial gallon ends up about 20% larger, which is also why UK imperial MPG figures read higher than US MPG for the same car.
How many fluid ounces are in a standard 750 mL wine bottle?+
About 25.36 US fluid ounces (750 mL ÷ 29.5735 mL per fl oz) — roughly five standard 5-oz pours per bottle.
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<a href="https://everyfix.net/tools/volume-converter/">Volume Converter</a> by <a href="https://everyfix.net">EveryFix</a>Related Tools
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