Convert fluid ounces to gallons
Fluid ounce (fl oz) to gallon (gal). One fluid ounce equals 0.007813 gallons.
Formula
Fluid ounce to gallon conversion table
| Fluid ounces | Gallons | Gallons | Fluid ounces |
|---|---|---|---|
| 1 fl oz | 0.007813 gal | 1 gal | 128 fl oz |
| 2 fl oz | 0.015625 gal | 2 gal | 256 fl oz |
| 3 fl oz | 0.023437 gal | 3 gal | 384 fl oz |
| 5 fl oz | 0.039063 gal | 5 gal | 640 fl oz |
| 10 fl oz | 0.078125 gal | 10 gal | 1280 fl oz |
| 20 fl oz | 0.15625 gal | 20 gal | 2560 fl oz |
| 50 fl oz | 0.390625 gal | 50 gal | 6400 fl oz |
| 100 fl oz | 0.78125 gal | 100 gal | 12800 fl oz |
| 500 fl oz | 3.9063 gal | 500 gal | 64000 fl oz |
| 1000 fl oz | 7.8125 gal | 1000 gal | 128000 fl oz |
To convert fluid ounces to gallons, divide the number of fluid ounces by 128. One fluid ounce equals 0.007813 gallons, and one gallon equals 128 fluid ounces, so the relationship is fixed and exact. As a worked example, 10 fl oz comes to 0.078125 gal. Enter your own figure in the converter above to get an instant answer, or use the swap button to flip the direction. This is a volume conversion, and like every tool on UnitGlide it runs locally in your browser with no account or upload required. The table further down shows a range of common fluid ounce values already worked out in gallons, plus the reverse gallon to fluid ounce direction, which is handy for quick reference or double-checking a result by hand.
Frequently asked questions
How many gallons are in a fluid ounce?
One fluid ounce equals 0.007813 gallons. The ratio is constant, so you can multiply any number of fluid ounces by 0.007813 to get gallons.
What is the formula to convert fluid ounces to gallons?
Use gallons = fluid ounces ÷ 128. UnitGlide applies this exact formula for every value, so results stay accurate across the whole range.
How do I convert gallons back to fluid ounces?
Go the other way by using one gallon equals 128 fluid ounces. You can also press the swap button in the converter above to flip the direction in one click.
Is this fluid ounce to gallon converter accurate?
Yes. It uses internationally defined SI conversion factors, as maintained by the BIPM, and all math runs in your browser so nothing is rounded away on a server. For everyday use the displayed precision is more than enough.