gallons to fluid ounces Converter

1 gal = 128 fl oz. Enter a value. The result updates immediately.

Convert

128 fl oz1 gal = 128 fl oz
Quick answer 1 gal = 128 fl oz gallons to fluid ounces uses this formula: fl oz = gal x 128

Accuracy and rounding

Best use

For liquid containers, nutrition labels, and recipe scaling.

Accuracy

Metric volume units are fixed, and cups, teaspoons, tablespoons, pints, quarts, and gallons use U.S. liquid measures unless imperial is named.

Rounding

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

  1. Enter the value in gallons.
  2. Select gallons as the source unit.
  3. Select fluid ounces as the target unit.
  4. Read or copy the result.

gallons to fluid ounces chart

gallonsfluid ounces
1 gal128 fl oz
2 gal256 fl oz
5 gal640 fl oz
10 gal1,280 fl oz
25 gal3,200 fl oz
50 gal6,400 fl oz
100 gal12,800 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.

Reference definition · Conversion methodology

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.

Related converters