How to convert us gallons to fluid ounces
To convert us gallons to fluid ounces, multiply the value by the conversion factor 128. To go the other way, multiply by 0.0078125 (or divide by 128).
Worked example: 25 gal to fl oz
- Write the value: 25 gal
- Multiply by 128: 25 × 128
- Result: 3,200 fl oz
US Gallon to Fluid Ounce (US) conversion table
Quick reference values, rounded to 6 significant digits.
| US Gallon (gal) | Fluid Ounce (US) (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 |
| 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 |
Fluid Ounce (US) to US Gallon
| fl oz | gal |
|---|---|
| 1 fl oz | 0.0078125 gal |
| 5 fl oz | 0.0390625 gal |
| 10 fl oz | 0.078125 gal |
| 50 fl oz | 0.390625 gal |
| 100 fl oz | 0.78125 gal |
1 US Gallon in other volume units
About US Gallon and Fluid Ounce (US)
What is a us gallon (gal)?
A US liquid gallon is exactly 3.785411784 liters, used for fuel and milk in the United States.
What is a fluid ounce (us) (fl oz)?
A US fluid ounce is about 29.57 mL, used for drinks and cosmetics labels.
Where us gallon to fluid ounce (us) conversion is used
Volume conversions are needed for cooking recipes, fuel, water tanks, beverages, medicine and shipping capacity. Converting between us gallons and fluid ounces is especially common when you compare products, read foreign specifications, or fill in forms that expect a specific unit.
Need every unit at once? Use the full Volume Converter.
Frequently asked questions
How many fluid ounces are in 1 us gallon?
1 US Gallon equals 128 fl oz.
How do I convert us gallons to fluid ounces?
Multiply the number of us gallons by 128. For example, 25 gal × 128 = 3,200 fl oz.
What is 25 gal in fl oz?
25 gal = 3,200 fl oz.
How many us gallons are in 1 fluid ounce (us)?
1 Fluid Ounce (US) equals 0.0078125 gal. Use the Fl Oz to Gallon converter for the reverse direction.
Is this US Gallon to Fluid Ounce (US) converter accurate?
Yes. It uses exact internationally defined conversion factors, calculated with full floating-point precision. Results are displayed rounded for readability.