In this conversion page, the tables and the converter are based on the US fluid gallons and the US fluid ounces.

How many fluid ounces in a gallon?

There are three types of gallons, US Customary fluid and dry gallons and the Imperial gallon. There are two types of fluid ounces, US Customary fluid ounce and the Imperial fluid ounce. So, depending on what types of gallons and fluid ounces are used, the answer to the question of how many ounces in a gallon might be different. If you are converting from US fluid gallons to fluid ounces, then there are 128 fluid ounces in a gallon. If the conversion is between Imperial gallons and Imperial fluid ounces, then there are 160 Imperial fluid ounces in an Imperial gallon.

The list of conversion factors from gallons to fluid ounces:

  • 1 US fluid gallon = 128 US fluid ounces
  • 1 Imperial gallon= 160 Imperial fluid ounces

How to convert gallons to ounces?

There are 128 ounces in a gallon. To convert gallons to ounces, multiply the gallon value by 128.

For example, to find out how many ounces there are in a half gallon, multiply 128 by 0.5, that makes 64 ounces in a half gallon.

gallons to fluid ounces formula:

fluid ounce = gallon * 128

Common conversions from gallons to fluid ounces (fl oz):

  • 1/8 gallon = 16 oz
  • 1/4 gallon = 32 oz
  • 1/3 gallon = 42.66 oz
  • 1/2 gallon = 64 oz
  • 2 gallons = 256 oz

To convert between imperial gallons and fluid ounces, please visit imperial gallons to fluid ounces converter.

How many water bottles are there in a gallon?

1 US gallon is equal to 128 US fluid ounces. To find out how many water bottles there are in gallons, multiply the number of gallons by 128 and divide by the size of the water bottle in fluid ounces.

For example, to find out how many 16.9 oz water bottles there are in 3 gallons, multiply 3 by 128 and divide by 16.9, that makes 22.72 water bottles of 16.9 oz in 3 gallons.

water bottles in a gallons:

  • there are 16 water bottles of 8 oz in a US gallon
  • there are 10.6 water bottles of 12 oz in a US gallon
  • there are 7.57 water bottles of 16.9 oz in a US gallon
  • there are 6.4 water bottles of 20 oz in a US gallon
  • there are 5.3 water bottles of 24 oz in a US gallon
  • there are 3.78 water bottles of 33.8 oz in a US gallon

To calculate how many water bottles of different sizes can fit in gallons and view the gallons to water bottles table, please visit how many water bottles are in gallons.

What is a Gallon?

Gallon is an imperial and United States Customary systems volume unit. 1 US gallon = 128 US fluid ounces. 1 Imperial gallon = 160 Imperial fluid ounces. The symbol is gal.

To convert from US fluid, dry and UK gallons to UK and US fluid ounces, please visit all volume units conversion.

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