Convert US fluid ounces to US gallons
Converting US fluid ounces to US gallons is a common volume task, whether you are checking a recipe, a spec sheet, a travel distance or a homework problem. Since 1 fl oz equals 0.0078125 gal, the math is a single multiplication — and this page does it for you instantly, with the formula, a table of common values and answers to the questions people ask most.
Exact factor
How to convert US fluid ounces to US gallons
To convert US fluid ounces to US gallons, multiply the number of US fluid ounces by 0.0078125. For example, 10 fl oz × 0.0078125 = 0.078125 gal.
gal = fl oz × 0.0078125
- Write down the value in US fluid ounces you want to convert.
- Multiply it by 0.0078125 (the exact fl oz→gal factor).
- The result is your value in US gallons. Check it below with the converter or the table.
Conversion table
Common values of US fluid ounces and their equivalents in US gallons:
| fl oz | gal |
|---|---|
| 1 | 0.0078125 |
| 2 | 0.015625 |
| 3 | 0.0234375 |
| 4 | 0.03125 |
| 5 | 0.0390625 |
| 10 | 0.078125 |
| 20 | 0.15625 |
| 25 | 0.195313 |
| 50 | 0.390625 |
| 100 | 0.78125 |
| 250 | 1.95313 |
| 500 | 3.90625 |
About these units
US Fluid Ounce (fl oz). The US fluid ounce is exactly 1/128 of a US gallon, or 29.5735295625 milliliters. Beverage cans, cosmetic bottles and cocktail recipes use fluid ounces.
US Gallon (gal). The US liquid gallon is defined as exactly 3.785411784 liters, or 128 US fluid ounces. Fuel economy and milk containers in the United States use gallons.
Frequently asked questions
How do I convert US fluid ounces to US gallons?
To convert US fluid ounces to US gallons, multiply the number of US fluid ounces by 0.0078125. For example, 10 fl oz × 0.0078125 = 0.078125 gal. Or skip the math: type the value into the converter at the top of this page and the result updates instantly.
How many US gallons are in 1 us fluid ounce?
1 fl oz = 0.0078125 gal. That is the fixed relationship used by this converter and by international standards.
How many US fluid ounces are in 1 us gallon?
1 gal = 128 fl oz. If you are converting in the opposite direction, use our US Gallon to US Fluid Ounce converter for the dedicated table and FAQ.
Is the US fluid ounces to US gallons conversion exact?
Yes. Both units are defined by international agreement, so the factor of 0.0078125 is exact. Displayed results are rounded to 6 significant digits only for readability.
What is us fluid ounce used for?
The US fluid ounce is exactly 1/128 of a US gallon, or 29.5735295625 milliliters. Beverage cans, cosmetic bottles and cocktail recipes use fluid ounces.