How many ounces are there in one gallon?

In the context of liquid measurement, one gallon is equivalent to 128 ounces. This conversion is based on the U.S. customary system where one gallon is defined as 4 quarts, and each quart contains 32 ounces. Therefore, when you calculate it out, you have:

1 gallon = 4 quarts × 32 ounces/quart = 128 ounces.

This understanding is essential, especially in bartending, where precise measurements are crucial for creating cocktails and managing inventory. Knowing that there are 128 ounces in a gallon helps bartenders measure correctly when prepping large batches of drinks or understanding how much a particular container can hold when mixing or storing beverages.