Gallons to Liters Converter

Type in either box to convert gallons to liters instantly, both ways.

1 gal = 3.78541 L

Runs entirely in your browser. Nothing you type is uploaded.

How to use this tool

This gallons to liters converter has two linked inputs. Type a number into the US gallons box and the liters box updates live, and the same works the other way around when you need to convert gal to L or back again. Use the Swap units button to flip the two values, which is handy when you are checking a US liquid capacity against a metric label, and Clear to reset both fields. Decimals are allowed, so 0.5, 2.5, or 12.75 all work fine.

The formula

liters = gallons x 3.78541 gallons = liters / 3.78541

One US liquid gallon equals exactly 3.78541 liters, so to convert gallons to liters you multiply by 3.78541. To go the other way you divide the liter value by the same number. This tool uses the US liquid gallon, not the imperial gallon used in the UK, which is larger at about 4.54609 liters. If you are reading a British or Canadian recipe, keep that difference in mind for your water volume conversion.

A real example

Say your car holds a 14 US gallon fuel tank and you want the size in liters for a trip abroad. Multiply 14 by 3.78541, which gives about 52.99 liters, so the tank is roughly 53 liters. Going the other way, a 2 liter soda bottle is 2 divided by 3.78541, which is about 0.53 gallons, just over half a US gallon.

Common volumes for reference

DescriptionUS gallonsLiters
Half gallon of milk0.5 gal1.89 L
One US gallon1 gal3.79 L
Two gallon bucket2 gal7.57 L
Five gallon water jug5 gal18.93 L
Ten gallon tank10 gal37.85 L
Average car fuel tank14 gal52.99 L
Fifty gallon drum50 gal189.27 L

Common questions

How many liters are in one US gallon?

One US liquid gallon equals 3.78541 liters. To convert any number of gallons to liters, multiply the gallon value by 3.78541.

What is the difference between US and imperial gallons?

This tool uses the US liquid gallon at 3.78541 liters. The imperial gallon used in the UK and Canada is larger, at about 4.54609 liters, so a US gallon is roughly 17 percent smaller than an imperial one.

How do I convert liters back to gallons?

Divide the liter value by 3.78541. For example, 10 liters divided by 3.78541 is about 2.64 US gallons. Just type the liter amount into the liters box and the gallons box fills in automatically.

Does this water volume converter work on my phone?

Yes. The layout reflows for phones, tablets, and desktops, and the tool runs fully in your browser, so it works the same on any device with no internet connection needed after the page loads.

How many decimal places does it show?

Results are rounded to five decimal places and trailing zeros are trimmed, so a clean value like 3.78541 shows in full while a whole number like 2 stays 2 rather than 2.00000.