Convert gallons to fluid ounces
fluid ounces = gallons × 128
One gallon is 128 fluid ounces, so multiply by 128 to convert. That factor is exact by definition. These are US customary measures. An imperial (UK) gallon is 4.54609 L against the US gallon's 3.785411784 L, and the imperial pint, quart and fluid ounce differ too, so UK figures will not match. This is the US fluid ounce of 29.5735 mL. An imperial (UK) fluid ounce is 28.4131 mL — smaller, because there are 20 to an imperial pint rather than 16.
Convert any value
- Milliliters
- 3,785.411784 mL
- Cubic meters
- 0.003785 m³
- Teaspoons (US)
- 768 tsp
- Tablespoons (US)
- 256 tbsp
- Fluid ounces (US)
- 128 fl oz
- Cups (US)
- 16 cup
- Pints (US)
- 8 pt
- Quarts (US)
- 4 qt
- Gallons (US)
- 1 gal
- Cubic inches
- 231 in³
- Cubic feet
- 0.133681 ft³
- Cubic yards
- 0.004951 yd³
Assumptions
- US customary units (customary cup of 236.59 mL, US gallon of 3.785 L).
- Imperial units are shown in the table only.
| Measure | Equals |
|---|---|
| 1 teaspoon | 4.93 mL (metric tsp: 5 mL) |
| 1 tablespoon | 3 tsp = 14.79 mL = ½ fl oz |
| 1 fluid ounce | 2 tbsp = 29.57 mL |
| 1 cup | 8 fl oz = 16 tbsp = 236.59 mL (legal 'nutrition' cup: 240 mL) |
| 1 pint | 2 cups = 16 fl oz = 473.18 mL |
| 1 quart | 2 pints = 4 cups = 946.35 mL |
| 1 gallon | 4 quarts = 16 cups = 128 fl oz = 3.785 L |
| 1 liter | 4.227 cups = 33.81 fl oz = 1.0567 qt |
| Unit | US (mL) | Imperial (mL) |
|---|---|---|
| Fluid ounce | 29.57 | 28.41 |
| Cup | 236.59 | 284.13 |
| Pint | 473.18 | 568.26 |
| Quart | 946.35 | 1,136.52 |
| Gallon | 3,785.41 | 4,546.09 |
An imperial pint is 20 imperial fl oz; a US pint is 16 US fl oz. This converter uses US units.
gallons to fluid ounces table
| gallons | fluid ounces |
|---|---|
| 1 gallon | 128 fluid ounces |
| 2 gallons | 256 fluid ounces |
| 3 gallons | 384 fluid ounces |
| 4 gallons | 512 fluid ounces |
| 5 gallons | 640 fluid ounces |
| 10 gallons | 1,280 fluid ounces |
| 15 gallons | 1,920 fluid ounces |
| 20 gallons | 2,560 fluid ounces |
| 25 gallons | 3,200 fluid ounces |
| 50 gallons | 6,400 fluid ounces |
| 75 gallons | 9,600 fluid ounces |
| 100 gallons | 12,800 fluid ounces |
| 500 gallons | 64,000 fluid ounces |
| 1,000 gallons | 128,000 fluid ounces |
Other conversions
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1 gallon = 128 fluid ounces. Source: https://www.calculateitnow.dev/gallons-to-fl-oz