US gallons to US fluid ounces – US gallon to US fluid ounce Converter
1 gal = 128 fl oz
Formula
fl oz = gal × 128
US gallons to US fluid ounces conversion table
| US gallons (gal) | US fluid ounces (fl oz) |
|---|---|
| 0.5 gal | 64 fl oz |
| 1 gal | 128 fl oz |
| 2 gal | 256 fl oz |
| 3 gal | 384 fl oz |
| 5 gal | 640 fl oz |
| 10 gal | 1280 fl oz |
| 20 gal | 2560 fl oz |
| 25 gal | 3200 fl oz |
| 50 gal | 6400 fl oz |
| 75 gal | 9600 fl oz |
| 100 gal | 12800 fl oz |
| 250 gal | 32000 fl oz |
| 500 gal | 64000 fl oz |
| 1000 gal | 128000 fl oz |
| 5000 gal | 640000 fl oz |
US gallons and US fluid ounces are both volume units. One US gallon equals 128 US fluid ounces; enter any value above for an instant result, or use the table for common conversions.
Sanity-check examples
1 gal = 128 fl oz10 gal = 1280 fl oz2.5 gal = 320 fl oz
Common pitfalls and look-alike units
Gallons differ: the US gallon ≈ 3.78541 L while the imperial gallon ≈ 4.546 L — about 20% apart, so check which one a recipe or fuel figure means. A US cup (~236.6 mL) is also not the metric 250 mL cup.
Frequently asked questions
How many US fluid ounces are in a US gallon?
1 US gallon (gal) equals 128 US fluid ounce (fl oz).
How do I convert US gallons to US fluid ounces?
Multiply the US gallon value by 128 to get US fluid ounce — for example, 2 US gallons = 256 US fluid ounce.
How do I convert US fluid ounces back to US gallons?
1 US fluid ounce equals 0.0078125 US gallon. Use the swap button or the reverse conversion page linked on this page.