Convert US gallons to liters instantly, using the exact definition where one US gallon is 3.785411784 liters. This conversion is handy for fuel, water usage, aquariums, and any container quoted in gallons when you think in metric liters. Type any number of gallons and the liter value appears live as you type, carried to several decimals for accuracy. Be aware that a US gallon and an imperial (UK) gallon are different sizes, with the UK gallon about 4.546 liters, so this tool uses the US gallon, which is the more common request online. Multiplying by 3.785 by hand is easy to round wrong, so letting the tool handle it keeps you accurate. Everything runs locally in your browser, making it instant, private, and usable offline once the page has loaded.