How many ounces in a gallon?
The number of ounces in a gallon depends on whether you are using the US customary system or the British imperial system.
US Customary System
In the US, one gallon is equal to 128 US fluid ounces125.
British Imperial System
In the UK and other countries using the imperial system, one gallon is equal to 160 UK fluid ounces245.
It's important to note these differences to ensure accurate measurements, especially when converting between the two systems.