How to convert US gallons to US fluid ounces
fl oz = gal × 128Multiply the value in US gallons by 128. To go the other way, multiply by 0.0078125 (or divide by 128).
An US gallon is larger than an US fluid ounce: one US gallon contains 128 US fluid ounces.
Worked examples
- 1 US gallon1 gal × 128 = 128 fl oz
- 5 US gallons5 gal × 128 = 640 fl oz
- 10 US gallons10 gal × 128 = 1,280 fl oz
- 20 US gallons20 gal × 128 = 2,560 fl oz
- 100 US gallons100 gal × 128 = 12,800 fl oz
US gallons to US fluid ounces conversion table
Values are calculated by the conversion engine and rounded to 8 significant figures.
| US gallons (gal) | US fluid ounces (fl oz) |
|---|---|
| 0.1 gal | 12.8 fl oz |
| 0.25 gal | 32 fl oz |
| 0.5 gal | 64 fl oz |
| 1 gal | 128 fl oz |
| 2 gal | 256 fl oz |
| 3 gal | 384 fl oz |
| 4 gal | 512 fl oz |
| 5 gal | 640 fl oz |
| 6 gal | 768 fl oz |
| 7 gal | 896 fl oz |
| 8 gal | 1,024 fl oz |
| 9 gal | 1,152 fl oz |
| 10 gal | 1,280 fl oz |
| US gallons (gal) | US fluid ounces (fl oz) |
|---|---|
| 12 gal | 1,536 fl oz |
| 15 gal | 1,920 fl oz |
| 20 gal | 2,560 fl oz |
| 25 gal | 3,200 fl oz |
| 30 gal | 3,840 fl oz |
| 40 gal | 5,120 fl oz |
| 50 gal | 6,400 fl oz |
| 75 gal | 9,600 fl oz |
| 100 gal | 12,800 fl oz |
| 250 gal | 32,000 fl oz |
| 500 gal | 64,000 fl oz |
| 1,000 gal | 128,000 fl oz |
About the units
US gallon (gal)
Defined as 231 cubic inches, exactly 3.785411784 L. US fuel, milk and paint are sold by the gallon. Four quarts or 128 US fluid ounces. One US gallon equals 0.003785411784 cubic meters (m³).
US fluid ounce (fl oz)
One 128th of a US gallon: 29.5735295625 mL. Beverage cans and bottles in the US are labelled in fluid ounces. One US fluid ounce equals 0.00002957352956 cubic meters (m³).
Frequently asked questions
How many US fluid ounces are in one US gallon?
There are 128 US fluid ounces in one US gallon, and this value is exact by definition.
How do I convert US gallons to US fluid ounces?
Multiply the number of US gallons by 128. For example, 10 gal × 128 = 1,280 fl oz.
How many US gallons are in one US fluid ounce?
One US fluid ounce equals 0.0078125 US gallons. That is the reverse factor, 1 ÷ 128.
What is 10 US gallons in US fluid ounces?
10 gal = 1,280 fl oz.
Is this gal to fl oz converter accurate?
Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.