Volume Converter
Enter a volume, choose its unit and see it in eleven units at once: liters, milliliters, US gallons, quarts, pints, cups, fluid ounces, imperial gallons, cubic meters, cubic feet and cubic inches. US and imperial units are labeled, because they are not the same size.
Last updated November 4, 2026
Result
1 US gal = 3.7854118 L = 0.83267418 imp gal
| Unit | Volume |
|---|---|
| Liters | 3.7854118 L |
| Milliliters | 3,785.4118 mL |
| US gallons | 1 US gal |
| US quarts | 4 US qt |
| US pints | 8 US pt |
Exact definitions: 1 US gal = 3.785411784 L, 1 imperial gal = 4.54609 L. Results are rounded to 8 significant digits.
Show the work
Formula: liters = volume x liters per unit; target = liters / liters per target unit
- Entered: 1 US gal.
- Liters first: 1 US gal = 3.785411784 L, so 1 x 3.785411784 = 3.7854118 L.
- Liters: 3.7854118 L / 1 (1 L = 1 L) = 3.7854118 L.
- Milliliters: 3.7854118 L / 0.001 (1 mL = 0.001 L) = 3,785.4118 mL.
- US quarts: 3.7854118 L / 0.946352946 (1 US qt = 0.946352946 L) = 4 US qt.
- US pints: 3.7854118 L / 0.473176473 (1 US pt = 0.473176473 L) = 8 US pt.
- US cups: 3.7854118 L / 0.2365882365 (1 US cup = 0.2365882365 L) = 16 US cup.
- US fluid ounces: 3.7854118 L / 0.0295735295625 (1 US fl oz = 0.0295735295625 L) = 128 US fl oz.
- Imperial gallons: 3.7854118 L / 4.54609 (1 imp gal = 4.54609 L) = 0.83267418 imp gal.
- Cubic meters: 3.7854118 L / 1,000 (1 m³ = 1,000 L) = 0.0037854118 m³.
- Cubic feet: 3.7854118 L / 28.316846592 (1 ft³ = 28.316846592 L) = 0.13368056 ft³.
- Cubic inches: 3.7854118 L / 0.016387064 (1 in³ = 0.016387064 L) = 231 in³.
Result: 1 US gal = 3.7854118 L = 0.83267418 imp gal
How volume units convert
1 US gal = 3.785411784 L · 1 imp gal = 4.54609 L · 1 US fl oz = 29.5735295625 mL · 1 ft³ = 28.316846592 L
This converter holds every volume as liters. It multiplies your number by the liters in your unit, then divides by the liters in the unit you want, so any pair of the eleven units is two steps. The metric units are exact powers of ten: 1 L is 1,000 mL and 1 m³ is 1,000 L.
The US customary units all come from the gallon. One US gallon is 231 cubic inches, which is exactly 3.785411784 liters. A quart is a quarter of that, a pint an eighth, a cup a sixteenth and a fluid ounce a 128th, so 1 US gallon is 4 quarts, 8 pints, 16 cups and 128 fluid ounces. The imperial gallon is a different, larger unit defined as exactly 4.54609 liters. Cubic inches and cubic feet follow from the inch being exactly 25.4 mm: 1 in³ is 16.387064 mL and 1 ft³ is 1,728 in³, or 0.028316846592 m³.
See how we calculate for the formulas, sources and review schedule behind every calculator.
Also useful alongside this calculator: ML to Cups Calculator, Weight Converter and Length Converter.
US versus imperial: a caution
A US gallon and an imperial gallon are not the same. The imperial gallon (4.54609 L) is about 20% larger than the US gallon (3.785411784 L): 1 imperial gallon is about 1.2009 US gallons. A fuel economy figure, a recipe or a tank size quoted in gallons can differ by a fifth depending on the country.
The same applies to the other imperial units, which this tool does not list: an imperial pint, for example, holds 20 imperial fluid ounces and is larger than a US pint. When the source does not say US or imperial, check where it was written before you convert. Every gallon, quart, pint, cup and fluid ounce on this page is the US version unless it says imperial.
Liters to gallons and back
To change liters into US gallons, divide by 3.785411784, or multiply by about 0.2642. To change US gallons into liters, multiply by 3.785411784. A 50 L tank holds about 13.21 US gallons, and a 10 US gallon aquarium holds about 37.85 L.
For imperial gallons use 4.54609 in the same way: 50 L is about 11.0 imperial gallons.
Cups, pints and fluid ounces
In US cooking, 1 cup is 8 fluid ounces, 1 pint is 2 cups and 1 quart is 2 pints. A US cup is 236.5882365 mL, so recipes written in metric often round it to 240 mL or 250 mL. This converter uses the exact US figure.
A fluid ounce measures volume, not weight. Do not mix it with the ounce used on kitchen scales, because the weight of a cup depends on the ingredient.
Cubic meters, feet and inches
Cubic units measure the space an object fills, which suits boxes, rooms and engine sizes. A cubic meter is 1,000 liters. A cubic foot is about 28.32 liters or 7.48 US gallons, and a cubic inch is 16.387064 mL. A 2.0 L engine is about 122 cubic inches.
Precision and rounding
The factors are exact by definition, so the only rounding comes from showing the result. The converter shows up to 8 significant digits, which keeps very small values such as one milliliter in cubic meters readable. Round your final answer, not the steps in between.
How to use the Volume Converter
- Enter the volume as a number of 0 or more.
- Choose its unit, taking care to pick US or imperial gallons correctly.
- Read the volume in all eleven units, then use Copy, Print or Share.
Worked example
To convert 1 US gallon, multiply by 3.785411784 to get 3.785411784 liters. Divide by 0.2365882365 (one US cup in liters) to get exactly 16 cups, and by 0.0295735295625 to get exactly 128 fluid ounces. Dividing by 4.54609 shows that it is only about 0.8327 imperial gallons, which is why the two gallons must never be mixed.
| Volume | L | mL | gal | cup | fl oz | imp gal |
|---|---|---|---|---|---|---|
| 1 liter | 1 | 1,000 | 0.2642 | 4.2268 | 33.814 | 0.22 |
| 1 US gallon | 3.7854 | 3,785.4118 | 1 | 16 | 128 | 0.8327 |
| 1 imperial gallon | 4.5461 | 4,546.09 | 1.2009 | 19.2152 | 153.7216 | 1 |
| 1 US cup | 0.2366 | 236.5882 | 0.0625 | 1 | 8 | 0.052 |
| 500 mL | 0.5 | 500 | 0.1321 | 2.1134 | 16.907 | 0.11 |
Frequently asked questions
How many liters are in a US gallon?
Exactly 3.785411784 liters. That is 231 cubic inches, and it is smaller than the imperial gallon of 4.54609 liters.
What is the difference between a US and an imperial gallon?
The imperial gallon is 4.54609 liters and the US gallon is 3.785411784 liters, so the imperial one is about 20% larger.
How many cups and fluid ounces are in a US gallon?
A US gallon is 16 cups, 8 pints, 4 quarts or 128 US fluid ounces. One US fluid ounce is 29.5735295625 mL.
How many liters are in a cubic foot?
One cubic foot is exactly 28.316846592 liters, which is about 7.48 US gallons or 1,728 cubic inches.
Can I convert a negative volume?
No. A volume is 0 or more, so the converter shows an error for negative values instead of a result.