Convert volume units — liters, gallons, cups, milliliters, cubic meters, pints, quarts.
| Unit | Name | Value |
|---|---|---|
| L | Liter | 3.78541 |
| mL | Milliliter | 3785.41 |
| m³ | Cubic Meter | 0.00378541 |
| gal(UK) | UK Gallon | 0.83267379 |
| qt | US Quart | 3.9999979 |
| pt | US Pint | 8.0000042 |
| cup | US Cup | 16.000008 |
| fl oz | Fluid Ounce | 128.00007 |
Common us gallon values converted to fluid ounce — factor: 1 gal = 128 fl oz
| US Gallon (gal) | Fluid Ounce (fl oz) | Context |
|---|---|---|
| 0.0078 gal | 0.9984 fl oz | Tablespoon |
| 0.031 gal | 3.968 fl oz | Quarter cup |
| 0.0625 gal | 8 fl oz | Cup |
| 0.125 gal | 16 fl oz | Pint |
| 0.25 gal | 32 fl oz | Quart |
| 0.5 gal | 64 fl oz | Half gallon |
| 1 gal | 128 fl oz | Gallon jug |
| 2 gal | 256 fl oz | Two gallons |
| 5 gal | 640 fl oz | Jerrycan |
| 10 gal | 1,280 fl oz | 10-gallon drum |
| 20 gal | 2,560 fl oz | 20-gallon tank |
| 42 gal | 5,376 fl oz | Oil barrel |
| 55 gal | 7,040 fl oz | Drum barrel |
| 100 gal | 1.28e+04 fl oz | Large drum |
| 1,000 gal | 1.28e+05 fl oz | Tank |
Converting us gallon to fluid ounce comes up frequently in cooking, chemistry, medicine, and engineering. A recipe written in metric units may need to be adapted for a kitchen using fluid ounce, or a laboratory protocol may specify volumes in us gallon that need to be measured with equipment calibrated in fluid ounce.
In everyday use, knowing that 5 gal = 640 fl oz and 10 gal = 1280 fl oz covers most common situations. For bulk calculations, 100 gal = 1.28e+04 fl oz is a useful anchor. The reverse conversion — fluid ounce back to us gallon — uses the factor 0.007812, so 1 fl oz = 0.007812 gal.
All conversions use the internationally recognized factor of exactly 1 gal = 128 fl oz. Calculations are performed in IEEE 754 double-precision floating point, giving accuracy to at least 8 significant figures — more than sufficient for any practical application.
Formula: Fluid Ounce = US Gallon × 128.00007
Multiply any us gallon value by 128.00007 to get fluid ounce. One us gallon equals 128.00007 fl oz.
Reverse: US Gallon = Fluid Ounce × 0.0078124959
US gallons × 128 = fluid ounces. One gallon = exactly 128 fl oz.
½ gal = 64 fl oz, ¼ gal = 32 fl oz = 1 qt.
fl oz ÷ 128 = gallons.
Prices fuel in USD per gallon and tracks daily sales volume in thousands of gallons.
Calculates pesticide and fertilizer application rates in gallons per acre.
Measures pool volume in gallons to calculate chlorine and pH chemical dosages.
Purchases engine oil, transmission fluid, and coolant in quart and gallon containers.
Estimates coverage (one US gallon covers about 350 sq ft) and quotes by the gallon.
Specifies water heater tank capacity (40, 50, 80 gallons) for residential systems.
The US liquid gallon is defined as exactly 231 cubic inches, or 3.785411784 liters. It traces its origins to the Queen Anne wine gallon of 1707, which American colonies adopted.
The US gallon differs from the UK Imperial gallon by about 16.5%. This matters for fuel economy: a US MPG figure is lower than the equivalent UK MPG for the same car.
Interesting fact: The United States, Liberia, and Myanmar are the only countries using the US gallon as a primary everyday volume unit.
The US fluid ounce is defined as 1/128 of a US gallon, exactly 29.5735 mL. The US and UK fl oz differ: the US is 29.57 mL while the Imperial fl oz is 28.41 mL.
Fluid ounces appear on every US beverage container: a soda can is 12 fl oz, a water bottle is 16.9 fl oz, and a US shot glass is 1.5 fl oz.
Interesting fact: Despite sharing the name 'ounce', the fluid ounce measures volume, not weight. One fl oz of water weighs about 1.04 oz, but one fl oz of honey weighs about 1.5 oz.