Convert US Fluid Ounce to US Gallon
Convert us fluid ounces to us gallons instantly. 1 us fluid ounce = 0.0078125 us gallon — use the live calculator, the exact formula, a conversion table and worked examples. Also check the US Gallon to US Fluid Ounce converter for the reverse conversion.
Units explained
US Fluid Ounce
A US fluid ounce is 1/128 of a US gallon (29.5735 mL).
Derived from the gallon subdivision; distinct from the slightly smaller UK fluid ounce.
Standard for US beverage and nutrition labeling.
English customary; US since 1824.
US Gallon
The US liquid gallon is defined as exactly 231 cubic inches (3.785411784 liters).
Based on the English wine gallon of 231 cubic inches, retained by the US after 1824.
The primary US unit for fuel, milk and large beverage containers.
English wine gallon; US since 1824.
US Fluid Ounce to US Gallon conversion formula
The relationship between us fluid ounces and us gallons:
To convert us fluid ounces to us gallons, multiply the value in us fluid ounces by 0.0078125. To reverse, multiply us gallons by 128.
How to use this converter
Type a value into the calculator. The result in us gallons updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the US Gallon to US Fluid Ounce converter for the reverse direction.
Step-by-step: convert us fluid ounces to us gallons
- Write down the value in us fluid ounces (fl oz).
- Multiply that value by the factor 0.0078125.
- The product is the equivalent value in us gallons (gal).
- To reverse, multiply the us gallon value by 128.
Worked examples
Example 1 — Convert 1 fl oz to gal:
1 × 0.0078125 = 0.0078125 gal
Example 2 — Convert 100 fl oz to gal:
100 × 0.0078125 = 0.78125 gal
Real-world example — Packaging gauge
A 4-us fluid ounce plastic bag thickness is a common spec for grocery and freezer bags. Converting from us fluid ounces to us gallons is what packaging buyers do whenever they bridge US and metric supplier quotes.
4 fl oz × 0.0078125 = 0.03125 gal
Real-world example — Plastic film and laminate thickness
A 500-us fluid ounce sheet is a typical spec for ID-card laminates and film overlays. Converting to us gallons aligns the value with the unit most CAD systems and material datasheets prefer.
500 fl oz × 0.0078125 = 3.90625 gal
US Fluid Ounce to US Gallon conversion table
Standard reference values for converting us fluid ounces to us gallons:
| US Fluid Ounce [fl oz] | US Gallon [gal] |
|---|---|
| 0.01 | 7.8125e-5 |
| 0.1 | 0.00078125 |
| 1 | 0.0078125 |
| 2 | 0.015625 |
| 3 | 0.0234375 |
| 4 | 0.03125 |
| 5 | 0.0390625 |
| 10 | 0.078125 |
| 20 | 0.15625 |
| 30 | 0.234375 |
| 40 | 0.3125 |
| 50 | 0.390625 |
| 100 | 0.78125 |
| 500 | 3.90625 |
| 1000 | 7.8125 |
Frequently asked questions
How many us gallons is 1 us fluid ounce?
How do I convert us fluid ounces to us gallons?
How do I convert us gallons back to us fluid ounces?
How many us gallons is 100 us fluid ounces?
Popular volume unit conversions
Convert US Fluid Ounce to other volume units
Show all US Fluid Ounce conversions
Metric / SI (8 units)
US Customary (Liquid) (7 units)
Imperial (UK) (4 units)
Cubic (length-derived) (3 units)
Cooking / Culinary (3 units)
Sources & references
Conversion factor (1 fl oz = 0.0078125 gal) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.