Volume
gallons to fluid ounces Converter
1 gal = 128 fl oz. Enter any value and the result updates instantly.
Convert
Accuracy and rounding
For liquid containers, nutrition labels, and recipe scaling.
Metric volume units are fixed, and cups, teaspoons, tablespoons, pints, quarts, and gallons use U.S. liquid measures unless imperial is named.
For recipes, round to the nearest useful spoon, cup, or milliliter. For containers and dosing, keep more precision in fluid ounces.
How to convert gallons to fluid ounces
- Type the gallons value in the calculator.
- Keep gallons selected as the from unit and fluid ounces selected as the to unit.
- Use the instant result, or copy it with the copy button.
gallons to fluid ounces chart
| gallons | fluid ounces |
|---|---|
| 1 gal | 128 fl oz |
| 2 gal | 256 fl oz |
| 5 gal | 640 fl oz |
| 10 gal | 1,280 fl oz |
| 25 gal | 3,200 fl oz |
| 50 gal | 6,400 fl oz |
| 100 gal | 12,800 fl oz |
Formula
fl oz = gal x 128
Example: 1 gal = 128 fl oz.
Source
Liter, cubic meter, and U.S. customary liquid measure relationships.
Common questions
How do I convert gallons to fluid ounces?
Enter the gallons value in the converter, or multiply by the factor shown in the formula. 1 gal = 128 fl oz.
What should I watch out for?
U.S. liquid units are used for cups, teaspoons, tablespoons, pints, quarts, and gallons unless the page says imperial.
Where does this volume conversion come from?
Liter, cubic meter, and U.S. customary liquid measure relationships. ConverterBase uses stable definitions and fixed conversion factors, not live or rounded market data.