US Gallons to Cups Converter

How to convert US Gallons to Cups

To convert US Gallons to Cups, multiply the value in US Gallons by 16.000008. For example, 5 gal = 80.000042 cup.

The US Gallons-to-Cups conversion comes up often in everyday and professional contexts alike. With 1 gal equal to 16.000008 cup, you can use the tool above for any value, or scan the table below for the most common US Gallons amounts and their Cups equivalents.

Volume conversions are essential in the kitchen, in science, and in any situation involving liquids or capacity. They're also one of the trickiest areas because US and UK (imperial) measurements share names but differ in size.

Understanding US Gallons and Cups

A US gallon (3.785 liters) is noticeably smaller than a UK gallon (4.546 liters) — about 20% less. The same applies to pints, quarts, and fluid ounces. Cups, tablespoons, and teaspoons are the backbone of recipe measurement, while liters and milliliters dominate scientific and most international contexts. This US/UK split is the single biggest source of error in volume conversion.

How accurate is this conversion?

Volume conversions here use the internationally accepted definitions: the US gallon is exactly 3.785411784 liters and the imperial gallon is exactly 4.54609 liters. Always confirm which system a recipe or specification uses before converting.

All conversion factors on ClearUnits are based on internationally recognised standards (the International System of Units, SI, and official definitions). Factors are reviewed for accuracy and the calculator uses full-precision values, rounding only the displayed result.

Quick reference: common US Gallons to Cups values

The most frequently searched conversions are 1 US Gallons = 16.000008 Cups, 5 US Gallons = 80.000042 Cups, 10 US Gallons = 160.00008 Cups, and 100 US Gallons = 1,600.001 Cups. The full table further down covers every common value, and the calculator handles any number you need in between.