US Gallons to US Fluid Ounces
1 US Gallon = 128 US Fluid Ounces
Common amounts:
About the us gallon to us fluid ounce conversion
The us gallon (gal (US)) and the us fluid ounce (fl oz (US)) are both units of volume. Convert between volume units — milliliters, liters, US and UK gallons, quarts, pints, cups and fluid ounces.
To convert us gallons to us fluid ounces, multiply by 128. To go back, multiply us fluid ounces by 0.0078125.
Reference table
| US Gallons | US Fluid Ounces |
|---|---|
| 1 gal (US) | 128 fl oz (US) |
| 5 gal (US) | 640 fl oz (US) |
| 10 gal (US) | 1,280 fl oz (US) |
| 25 gal (US) | 3,200 fl oz (US) |
| 50 gal (US) | 6,400 fl oz (US) |
| 100 gal (US) | 12,800 fl oz (US) |
Need the reverse conversion? Convert US Fluid Ounces to US Gallons.
Convert US Gallon to other volume units
Frequently asked questions
- How many us fluid ounces is 1 us gallon?
- 1 US Gallon equals 128 US Fluid Ounces. To go the other way, 1 US Fluid Ounce equals 0.0078125 US Gallons.
- What's the formula to convert us gallons to us fluid ounces?
- Multiply the number of us gallons by 128 to get us fluid ounces. For example, 10 us gallons × 128 = 1,280 us fluid ounces.
- Does this converter handle decimals and very large numbers?
- Yes. Type any real number, including decimals or values in the trillions. Math runs entirely in your browser — no server round-trip, no sign-up, and nothing to install.