How many fluid ounce are in one gallon (us)?
One gallon (us) is 128 fl oz.
Gallon (US) to Fluid ounce
Type a value to convert it from gallon (us) to fluid ounce. One gal equals 128 fl oz.
Result
Gallon (US) and Fluid ounce, side by side
One gallon (us) is 128 fl oz. In the other direction, one fluid ounce is 0.007813 gal.
The factor is exact rather than rounded: the imperial units have been defined from the metric ones since 1959, so the conversion introduces no error of its own. What you see below is arithmetic, not an approximation.
| Gallon (US) | Fluid ounce |
|---|---|
| 1 | 128 |
| 2 | 256 |
| 5 | 640 |
| 10 | 1280 |
| 20 | 2560 |
| 50 | 6400 |
Frequently asked questions
How do I convert fluid ounce back to gallon (us)?
One fluid ounce is 0.007813 gal. The tool above converts in both directions.
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