A US fluid ounce is 1/128 of a US gallon, equal to about 29.57 milliliters.
Fluid ounce to Gallon
Convert Fluid ounce to Gallon instantly. Free online cooking unit converter with exact formula, conversion table and FAQ.
Reserved for a responsive leaderboard above the conversion details.
Professional calculator style
World-scale conversion engine
30+ categories
6,500+ units
Instant results
Offline ready
Converter
Cooking Converter
Convert cooking volume and mass units used in recipes and nutrition workflows.
Context values
Some unit families need one extra value for a physically accurate result.
A US liquid gallon equals 4 US quarts, or exactly 3.785411784 liters.
gal = fl oz × 0.0078125
Results update instantly for Fluid ounce to Gallon conversions.
Reserved above the conversion cards and below the converter.
Formula
gal = fl oz × 0.0078125
fl oz = gal × 128
Conversion table
| 1 fl oz | 0.007812 gal |
| 5 fl oz | 0.039062 gal |
| 10 fl oz | 0.078125 gal |
| 20 fl oz | 0.15625 gal |
| 50 fl oz | 0.390625 gal |
| 100 fl oz | 0.78125 gal |
| 500 fl oz | 3.90625 gal |
| 1000 fl oz | 7.8125 gal |
Related conversions
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
What is the source unit in this conversion?
The source unit is the fluid ounce (fl oz). A US fluid ounce is 1/128 of a US gallon, equal to about 29.57 milliliters.
What is the destination unit in this conversion?
The destination unit is the gallon (gal). A US liquid gallon equals 4 US quarts, or exactly 3.785411784 liters.
How do I convert fluid ounce to gallon?
Multiply the fluid ounce value by 0.0078125. For example, 10 fl oz × 0.0078125 = 0.078125 gal.
Is the fluid ounce to gallon conversion exact?
Yes. This conversion uses a fixed factor defined for cooking measurement standards, so results are consistent every time.
Where is this conversion commonly used?
It's used when following recipes, adjusting ingredient quantities, or converting between US customary and metric cooking measurements.
Can I convert gallon back to fluid ounce?
Yes. Multiply the gallon value by 128 to get fluid ounce.
Reserved between the FAQ and the article so the page stays balanced.
About this conversion
This page converts fluid ounce (fl oz) to gallon (gal) within the cooking converter.
A US fluid ounce is 1/128 of a US gallon, equal to about 29.57 milliliters. A US liquid gallon equals 4 US quarts, or exactly 3.785411784 liters.
The formula is gal = fl oz × 0.0078125, based on each unit's fixed relationship to the cooking converter's reference units.
Results are consistent because the conversion relies on a fixed numerical ratio rather than an estimate.
Use the calculator above for instant results, or the table below for common fluid ounce values already converted to gallon.