Convert US gallon to litre

1 US gallon = 3.785412 litres. Enter any value below for an exact conversion.

Value in US gallons

1 gal =

3.785412 L

litres

Need the reverse? Convert litre to US gallon →

Formula

1 US gallon = 3.785412 litres
litre = US gallons × 3.785412
US gallon = litres × 0.2641721

US gallon to litre conversion table

1 gal3.785412 L

2 gal7.570824 L

3 gal11.35624 L

5 gal18.92706 L

10 gal37.85412 L

20 gal75.70824 L

25 gal94.63529 L

50 gal189.2706 L

100 gal378.5412 L

1000 gal3785.412 L

About converting US gallons to litres

US gallons to litres comes up for fuel, aquariums, and recipes when converting US measures to metric. Multiply gallons by 3.785 to get litres; the US gallon differs from the imperial gallon used in the UK.

Method & sources

Conversions use exact legal definitions rather than rounded approximations: 1 inch = 2.54 cm and 1 pound = 0.45359237 kg (fixed by the 1959 international yard and pound agreement), 1 mile = 1.609344 km, and 1 US liquid gallon = 3.785411784 litres. Temperatures convert with °F = °C × 9⁄5 + 32 and K = °C + 273.15. Results are rounded only for display.

Page last updated: October 1, 2026

Frequently asked questions

How many litres are in a US gallon?

One US gallon equals 3.785412 litres. So 10 US gallons is 37.85412 litres. Use the converter above for any value.

What is the formula to convert US gallons to litres?

1 US gallon = 3.785412 litres litre = US gallons × 3.785412 US gallon = litres × 0.2641721

Is the US gallon-to-litre conversion exact?

Yes. The conversion factor between US gallons and litres is defined exactly, so results are precise — only rounded for display.

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