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Gallons to Fluid Ounces

Convert gallons (gal) to fluid ounces (fl oz) — instant and accurate

1 gal = 128 fl oz  ·  To convert gallons to fluid ounces, multiply by 128.

128 fl oz

Gallons to Fluid Ounces Conversion Table

GallonsFluid Ounces
0.25 gal32 fl oz
0.5 gal64 fl oz
1 gal128 fl oz
2 gal256 fl oz
3 gal384 fl oz
4 gal512 fl oz
5 gal640 fl oz
6 gal768 fl oz
8 gal1024 fl oz
10 gal1280 fl oz
16 gal2048 fl oz
25 gal3200 fl oz
50 gal6400 fl oz
100 gal12800 fl oz
250 gal32000 fl oz
500 gal64000 fl oz
1000 gal128000 fl oz

Formula

fluid ounces = gallons × 128
gallons = fluid ounces × 0.0078125
Example: 5 gal × 128 = 640 fl oz

About the Gallons-to-Fluid Ounces Conversion

Converting gallons to fluid ounces comes up most often when interpreting measurements or specifications across different contexts. Gallons is widely used for fuel, milk, paint, and large liquid quantities in the United States; fluid ounces is the standard for beverages, recipes, and personal-care products in the United States. Both units belong to the US customary system. One gal equals 128 fl oz.

Real-World Examples

  • 0.25 gal (0.25 gallons) = 32 fl oz
  • 8 gal (8 gallons) = 1024 fl oz
  • 1000 gal (1000 gallons) = 128000 fl oz

Fluid Ounces to Gallons (Reverse)

Fluid OuncesGallons
0.25 fl oz0.00195312 gal
0.5 fl oz0.00390625 gal
1 fl oz0.0078125 gal
2 fl oz0.015625 gal
3 fl oz0.0234375 gal
4 fl oz0.03125 gal
5 fl oz0.0390625 gal
6 fl oz0.046875 gal
8 fl oz0.0625 gal
10 fl oz0.078125 gal
16 fl oz0.125 gal
25 fl oz0.195312 gal
50 fl oz0.390625 gal
100 fl oz0.78125 gal
250 fl oz1.95312 gal
500 fl oz3.90625 gal
1000 fl oz7.8125 gal

Frequently Asked Questions

How many fluid ounces are in a gallon?

1 gallon equals 128 fluid ounces.

How do I convert gallons to fluid ounces?

Multiply the value in gallons by 128 to get fluid ounces. For example, 5 gal × 128 = 640 fl oz.

How do I convert fluid ounces back to gallons?

Multiply the value in fluid ounces by 0.0078125 to get gallons. Equivalently, divide by 128.

How many gallons are in a fluid ounce?

1 fluid ounce equals 0.0078125 gallons.

Is the gallons-to-fluid ounces conversion exact?

Yes. 1 gal = 128 fl oz is an exact value defined by international agreement.

About Gallons and Fluid Ounces

The US liquid gallon (symbol gal) equals 4 quarts, 8 pints, or exactly 3.78541 liters. The UK imperial gallon is about 20% larger (4.546 L).

The US fluid ounce (symbol fl oz) equals 2 tablespoons, or exactly 29.5735 milliliters. It is distinct from the UK fluid ounce, which is slightly larger.

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