Method and practical guide
Volume conversion for liters, cubic meters, and US gallons
Convert liquid capacity, container sizes, and spatial volume using liters, milliliters, cubic meters, and common US customary units.
How it is calculated
Liters are the reference. Cubic and capacity units use defined relationships, such as one cubic meter equaling 1,000 liters.
Reference values
- 1 liter = 1,000 milliliters
- 1 cubic meter = 1,000 liters
- 1 US gallon = 3.785411784 liters
- 1 US cup = 236.5882365 milliliters
Worked examples
- 2.5 liters = 2,500 milliliters
- 0.75 m³ = 750 liters
- 5 US gallons is about 18.9271 liters
Common uses
Cooking, tank capacity, fuel use, and imported packaging frequently use different volume units.
Accuracy and scope
This tool uses US gallons, quarts, and cups. Imperial gallons are different, so confirm the standard used by the source material.