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⚡ US Gallons to US Fluid Ounces: the quick answer
1 gal = 128 fl oz
1 US gallon equals 128 US fluid ounces
To convert US gallons to US fluid ounces, multiply the value by 128.
To go the other way, multiply US fluid ounces by 0.0078125 to get US gallons.
↔ Convert US fluid ounces to US gallons instead
🧮 Formula
Every unit here is defined by its volume in cubic meters, so the conversion factor is (cubic meters per US gallon) ÷ (cubic meters per US fluid ounce).
📊 US Gallons to US Fluid Ounces conversion table
✏️ Worked examples
📘 About these units
US gallon (gal). The US liquid gallon is 231 cubic inches, exactly 3.785411784 liters.
US fluid ounce (fl oz). A US fluid ounce is 29.5735 mL, the unit on American drink and food labels.
❓ Frequently asked questions
How many US fluid ounces are in one US gallon?
There are 128 US fluid ounces in one US gallon.
How do I convert US gallons to US fluid ounces?
Multiply the number of US gallons by 128. For example, 10 US gallons equal 1,280 US fluid ounces.
How many US gallons are in one US fluid ounce?
One US fluid ounce equals 0.0078125 US gallons.
🔗 More volume conversions
All volume units →