Quarts
There is more than one kind of quart:
One US liquid quart is 946ml: US liquid quart
One UK quart is 1.14L: UK quart
US liquid gallons
A US liquid gallon is a volume measurement used in the United States for liquids such as water, gasoline, and milk. One US liquid gallon is about 3.78541 liters. A standard bathtub is about 80 gallons of water and a car gas tank can hold anywhere between 12 and 20 gallons of gas.