Converting gallons into pints, liters and quarts requires you to know something about both the metric system and the U.S. customary system of measurements. You will simply need to memorize some simple formulas to perform the task. Once you understand the basics, you can use an online converter to speed up the process.
Things You'll Need
 Calculator

Understand that 1 gallon equals 8 pt. So if you need to convert gallons to pints, simply multiply the number of gallons by eight. For example, if you have 3 gallons, you would multiply 3 by 8 to get 24 pt.

Multiply the number gallons you have by four to convert to quarts. For example, if you have 5 gallons, multiply 5 by 4 to get 20 quarts.

Convert gallons to liters by multiplying the number of gallons by 3.785. For example, if you have 8 gallons, you would multiply 8 by 3.785 to get 30.28 liters.

Doublecheck your calculations with an online calculator (see Resources).
Tips & Warnings
 Check your math with a calculator or an online metric conversion chart.
 Note that U.S. dry gallon volume measurements are different than liquid measurements. One U.S. dry gallon equals 4.405 liters.
References
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