Home/Converters/Gallons to Liters
Converters
Gallons to Liters
One US gallon is exactly 3.785412 litres. Multiply gallons by 3.785411784 for fuel economy, aquariums, and any label that says US gal.
1 gal = 3.7854 L
How to use it
- Type a value in US gallons. The litres result updates immediately.
- Read the full factor under the result if you need to check the math by hand.
- Use the table for the values people look up most often.
- Open the reverse converter when you already have litres.
Formula
litres = US gallons × 3.785411784
The US liquid gallon is exactly 231 cubic inches, which is 3.785411784 litres. An imperial gallon is about 4.54609 litres and is not used here.
Filling a 15 gallon tank
15 × 3.785411784 = 56.781 litres. If fuel is priced per litre, multiply that price by 56.781 for a full US 15 gallon tank.
A 15 gallon tank is 56.781 litres. A gallon of paint in the US is the same liquid gallon, about 3.785 litres, which is why a US gallon can covers less wall than a 5 litre tin. UK fuel consumption in miles per imperial gallon cannot be compared with US mpg using this factor alone, because the gallons differ.
Common gallons to liters values
| US gallons | litres |
|---|---|
| 1 gal | 3.7854 L |
| 5 gal | 18.9271 L |
| 10 gal | 37.8541 L |
| 15 gal | 56.7812 L |
| 20 gal | 75.7082 L |
| 50 gal | 189.2706 L |
Questions
How do I convert US gallons to litres?
Use litres = US gallons × 3.785411784. The converter applies that factor at full precision and rounds only what it displays.
Is this gallons to liters factor exact?
The US liquid gallon is exactly 231 cubic inches, which is 3.785411784 litres. An imperial gallon is about 4.54609 litres and is not used here.
How many litres are in a US gallon?
A US liquid gallon is exactly 3.785411784 litres. An imperial gallon is larger, about 4.546 litres.
Does ProHacks store the number I type?
No. The conversion runs in your browser. The value is not uploaded with the calculation.