Gallons to Liters Converter

The converter above is already set to gallons and liters, so you only need to enter your number. The result updates as you type, and nothing is sent anywhere.

1. Type your value in the Value box, for example 1. Decimals and negative numbers are accepted.
2. Check that From shows gallons and To shows liters. Both menus can be changed if you need a different pair.
3. Read the answer in the large result box. The note under it shows the exact factor used for one gallon.
4. Press Copy result to put the answer on your clipboard, or Swap units to convert in the opposite direction.
5. Look at In every unit on the right to see the same amount in all the other volume units.

One gallon is about 3.78541 liters, so the formula is liters = gallons x 3.78541. Going the other way, one liter is about 0.264172 gallons. A US gallon is exactly 3.785411784 liters, roughly 17 percent smaller than the imperial gallon of 4.546 liters. A liter is 1,000 milliliters, the volume of a cube 10 centimeters on each side.

Worked examples with the same factor:

• 1 gallon: 1 x 3.78541 = 3.78541 liters
• 3 gallons: 3 x 3.78541 = 11.3562 liters
• 10 gallons: 10 x 3.78541 = 37.8541 liters

Multiply by 3.8: 10 gallons is about 38 liters.

To check the converter by hand, take 3 gallons and apply the rule once: the result should be 11.3562 liters. If you go back again with the reverse factor 0.264172 you land on 3 gallons, which confirms that the two directions agree. Rounding the factor to fewer digits for mental math gives a result that is close but not identical, so use the tool when the last digits matter.

These reference values come from the same factor the converter uses, so they match what you see above. Use the table for common amounts, and the converter for anything else.

Volume units are the most confusing family because the same names mean different amounts in different countries. The US customary system and the British imperial system both use gallons, pints and fluid ounces, but they are not equal, and neither matches the metric cup used in many recipes. This converter uses US customary measures for gallons, cups, tablespoons, teaspoons and fluid ounces, and exact metric definitions for liters and milliliters.

Use the table as a sanity check rather than a substitute for the converter. A liter is a little more than a quart and a quarter of a US gallon, and a milliliter is a thousandth of a liter, so a result that is wildly different from those landmarks probably used the wrong unit. When a recipe matters, weigh the ingredient if the recipe gives a weight.

US fuel prices, tank capacities, paint and milk are measured in gallons, while most other countries use liters.

Measuring spoons and cups vary by country: a metric cup is 250 ml, a US legal cup is 240 ml and a US customary cup is 236.6 ml. For baking by weight, a scale is more consistent than any volume conversion because flour and sugar pack differently.

Related pages: Liters to Gallons Converter for the reverse direction, and the teaspoons to milliliters and milliliters to fluid ounces pages. For other volume units use the volume converter.

The page keeps no history, so each visit starts again from the defaults, 1 gallon. Your numbers are processed by JavaScript in your own browser and are never sent to a server, which makes the converter safe for private figures such as medical, financial or work measurements.