US Gallons to Liters Converter
Convert US Gallons to Liters with the exact conversion factor, a worked example and a quick-reference table. Runs entirely in your browser.
This converter turns US Gallons into Liters instantly using the standard definition of both units. It includes the formula, a worked example, and a quick table for common amounts, and it works for any value you type — including decimals and negatives where they make sense.
Quick reference — US Gallons to Liters
How to use this calculator
- Enter the value in US Gallons in the input box.
- Read the result in Liters — it updates as you type.
- Use the Swap button to convert in the opposite direction.
- Check the quick-reference table for common US Gallons amounts.
The formula
Liters = US Gallons × 3.78541
Worked example
5 gal = 18.9271 L — in full, 5 US Gallons converts to 18.9271 Liters. Fuel, drinks and tank sizes are the everyday jobs for this conversion.
Frequently Asked Questions
How do I convert US Gallons to Liters?
Multiply the value in US Gallons by 3.78541. For example, 5 US Gallons × 3.78541 = 18.9271 Liters. To go the other way, divide by 3.78541 instead — or press Swap in the converter above.
How many Liters are in one US Gallon?
One US Gallon equals 3.78541 Liters. Scaling up, 10 US Gallons = 37.8541 Liters and 100 US Gallons = 378.541 Liters. The converter uses the full-precision factor, so typed values are more precise than the rounded figure quoted here.
Which is bigger, a US Gallon or a Liter?
A US Gallon is bigger. One US Gallon equals 3.78541 Liters, while one Liter is only 0.264172 US Gallons. So a measurement that looks larger in Liters is reflecting the scale difference, not an error.
What is 5 US Gallons in Liters?
5 US Gallons is 18.9271 Liters. The math is 5 × 3.78541 = 18.9271. Try any other amount in the converter above and the result updates as you type.