Unlike most of the world, which relies on the metric system, the United States uses a non-uniform system for measuring and dispensing most liquids. A holdover from the system of imperial units of the British Empire, the "U.S. customary system" measures liquid from gasoline to groceries based on a quantity of fluid ounces. To efficiently manage formulas, recipes and calculate cost, it is necessary to understand the system for converting gallons, quarts, pints and cups.
Change cups into pints. Multiply the number of ounces in a cup, which is 8 ounces, by 2. With 1 pint holding 16 ounces, 1 pint is equal to 2 cups (2 x 8 = 16).
Convert cups or pints to quarts. As there are 32 ounces in a quart, a quart will hold 4 cups (4 x 8 = 32) or 2 pints (2 x 16 = 32).
Calculate the number of cup, pints or quarts in a gallon. With a gallon holding 128 ounces, a gallon is equal to 16 cups (16 x 8 = 128), 8 pints (8 x 16 = 128) or 4 quarts (4 x 32 = 128).