Convert US Gallon to Liter (gal (US) → L)

Converting US gallons to liters is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in US gallons

   Start with the number of US gallons (gal (US)) you want to convert.
2. 2
   Multiply by 3.785412

   The conversion factor from gal (US) to L is 3.785412. Multiply your value by this number.
3. 3
   Read the result in liters

   The result is your value in liters (L).

Multiply the value in US gallons by 3.785412. For the reverse direction, multiply by 0.264172.

• ✓1 US gallon = 3.785 L = 128 US fluid ounces = 4 quarts.
• ✓Converting mpg (US) to L/100 km: 235.215 / mpg = L/100 km.
• ✓The US gallon is based on the old English Queen Anne wine gallon (1707).

• ✗Using UK gallons on a US fuel-economy figure — 30 mpg (US) = 36 mpg (UK).
• ✗Confusing US gallon (3.79 L) with UK gallon (4.55 L) — 20% difference.
• ✗Using "gallon" without qualifier in cross-Atlantic commerce.

What is the US Gallon?

The US liquid gallon equals exactly 3.785411784 liters and is the standard volume unit for fuel, beverages, milk, and household liquids in the United States. Defined as 231 cubic inches, the US gallon descends from the English wine gallon of 1707, which Britain replaced with the larger imperial gallon in 1824 — a divergence that left the United States with a different gallon than the rest of the English-speaking world. American gas stations price gasoline by the gallon (typical fill-up: 12–15 gallons), milk is sold in half-gallons and gallons, and many beverages come in fluid-ounce subdivisions of the gallon. The US gallon relates to the liter (1 gal ≈ 3.785 L), the quart (4 qt = 1 gal), the pint (8 pt = 1 gal), the cup (16 cups = 1 gal), and the imperial gallon (1 imp gal ≈ 1.201 US gal — about 20% larger).

• US fuel pricing and consumption
• US paint, oil and cleaning-product packaging
• US beverage containers (1-gallon jugs of milk)

What is the Liter?

The liter equals exactly 1 cubic decimeter (1 dm³ = 0.001 m³) and is the everyday metric unit for liquids worldwide. Adopted as part of the metric system in the 1790s, the liter is used universally for beverages, fuel, household chemicals, and cooking liquids — except in the United States where gallons and fluid ounces dominate. The liter has special connection to mass: pure water at 4°C has almost exactly 1 kg per liter, a relationship designed into the metric system. Soda, milk, and water bottles in metric countries come in 0.5 L, 1 L, 1.5 L, and 2 L sizes. The liter relates to the milliliter (1,000 mL = 1 L), the cubic meter (1,000 L = 1 m³), the US gallon (1 L ≈ 0.264 gal), and the UK gallon (1 L ≈ 0.220 imp gal). Although not strictly an SI base unit, the liter is one of the most-used metric units globally.

• Bottled beverages and milk in Europe
• Petrol and diesel pricing in metric countries
• Engine displacement (car engines rated in litres)