1 Gallons to Ounces
1 gal = 128 fl oz
1 US gallon equals 128 US fluid ounces.
How to convert 1 gal to fl oz
Use the formula fl oz = gal × 128:
fl oz = 1 × 128fl oz = 128
So 1 gal = 128 fl oz.
Rounded values and quick estimate
- Rounded to a whole number: 128 fl oz
- Rounded to one decimal place: 128 fl oz
- Conversion factor: 1 US gallon = 128 US fluid ounces
This conversion is exact, so there is no need to estimate: just multiply by 128.
1 Gallons in other units
- US fluid ounces
- 128 fl oz
- Milliliters
- 3785.41 ml
- Liters
- 3.79 L
- Teaspoons
- 768 tsp
- Tablespoons
- 256 tbsp
- US cups
- 16 cups
- US pints
- 8 pt
- US quarts
- 4 qt
- Cubic centimeters
- 3785.41 cc
- Cubic inches
- 231 cu in
- Cubic feet
- 0.1337 cu ft
- Drops
- 75708.24 drops
- Oil barrels
- 0.0238 bbl
- UK gallons
- 0.8327 UK gal
- Cubic meters
- 0.003785 m³
- Cubic yards
- 0.004951 cu yd
1 gal and nearby values
About us gallons and us fluid ounces
A US gallon is 128 US fluid ounces, exactly 3.785411784 liters. (The UK imperial gallon is 4.546 liters.)
A US fluid ounce is 1/128 of a US gallon, about 29.57 ml. (A UK imperial fluid ounce is slightly smaller, 28.41 ml.)
Related conversions
Frequently asked questions
What is 1 Gallons in Ounces?
1 US gallon is 128 US fluid ounces (1 gal = 128 fl oz).
How do you convert 1 gal to fl oz?
Apply fl oz = gal × 128: fl oz = 1 × 128, fl oz = 128.
How many US gallons is 128 fl oz?
128 fl oz is about 1 US gallon.