Liters to Gallons

They are two different units that share a name. A US liquid gallon is defined as exactly 3.785411784 litres. A UK (Imperial) gallon is defined as exactly 4.54609 litres. The Imperial gallon is about 20% larger than the US gallon. The UK gallon is used in the United Kingdom, Canada (informally), and some Commonwealth countries; the US gallon is used in the United States. Always check which gallon your source uses — fuel economy figures in particular can look very different depending on whether they are in US mpg or UK mpg.

Divide the litre value by 3.785411784 for US gallons, or by 4.54609 for UK gallons. So 10 litres = 10 ÷ 3.785411784 ≈ 2.6417 US gallons, or 10 ÷ 4.54609 ≈ 2.1997 UK gallons. The converter does both at once so you do not have to remember which factor to use.

Close but no — it is a common rule-of-thumb that introduces error. 1 US gallon is 3.7854 litres (about 5.5% under 4 L). 1 UK gallon is 4.5461 litres (about 13.6% over 4 L). For rough mental math the 4 L approximation can work, but for anything that matters — fuel cost, recipe scaling, chemistry — use the exact factor.

1 US gallon = 3.785411784 litres. Common reference points: 5 US gallons ≈ 18.93 L, 10 US gallons ≈ 37.85 L, 20 US gallons ≈ 75.71 L, and a standard US car fuel tank of 12–15 gallons holds about 45–57 L.

1 UK gallon = 4.54609 litres exactly. 5 UK gallons ≈ 22.73 L, 10 UK gallons ≈ 45.46 L. The UK switched to litres for fuel sales decades ago, but Imperial gallons still appear in older recipes, motor publications, and miles-per-gallon (UK mpg) figures.

1 litre ≈ 0.264172 US gallons, or ≈ 0.219969 UK gallons. So a 1 L bottle of water is about a quarter of a US gallon.

Use US gallons when working with US-sourced data: fuel economy advertised in the US, US recipe books, US engineering specs, US cargo capacity. Use UK gallons for older British references, UK-published mpg figures, and some Commonwealth fuel contexts. For everything else — most of the world, most modern packaging, scientific work — the litre is the unit you actually need. The converter shows both gallons whenever you enter litres so you can pick whichever one matches the context you came from.

Both gallons descend from older English wine and ale gallons that varied widely. The United States standardised on the older Queen Anne wine gallon (231 cubic inches) at independence. The United Kingdom adopted the Imperial gallon in 1824, defining it as the volume of 10 lb of water at a specified temperature — which turned out to be a different, larger volume. The two definitions have stayed apart ever since, and there is no plan to align them.

Yes. The input accepts any positive decimal, so 1.5 L, 13.6 US gal, 0.473 L (a US pint) all work. Results are rounded to six decimal places, which is more than enough precision for any everyday use.

Yes. Completely free, no signup, no watermark, no ads on the result. All conversions happen in your browser — nothing you type is sent to a server.