Convert Liter to US Gallon

One US gallon equals exactly 3.785411784 liters — defined by the US gallon being 231 cubic inches and the inch being 25.4 mm. To convert liters to US gallons, divide by 3.785411784. A 10-liter jerry can holds 2.642 US gallons; a 40-liter petrol tank is 10.567 US gallons.

Fuel pricing is where this conversion matters most to travellers. European petrol stations price fuel per liter; American stations price it per US gallon. If unleaded costs €1.70/L in France and $3.80/gal in Ohio, the French price in US gallon terms is €1.70 × 3.785 = €6.43 per gallon — even before accounting for the exchange rate. The liter price always looks cheaper, which surprises American visitors until they multiply.

The critical gotcha is the two different gallons. The US gallon (3.785 L) and the Imperial gallon used in the UK (4.54609 L) are completely different units — the Imperial gallon is about 20% larger. UK fuel economy quoted in miles per gallon is therefore not directly comparable to US mpg. A British car getting 40 mpg (Imperial) returns the equivalent of only 33.3 mpg (US). Recipes from Canadian or British sources that list volumes in 'gallons' almost certainly mean Imperial gallons.

Cooking crossovers occasionally arise with American recipes calling for a gallon of stock or broth. A US gallon is about 3.785 L — just under four standard metric litre bottles, or eight US pints.