1 US gallon = 3.78541 liters (exact enough for everything). Multiply gallons by 3.78541; divide liters by 3.78541 to go back.
Quick chart
- 1 gal = 3.79 L
- 5 gal = 18.93 L
- 10 gal = 37.85 L
- 15 gal (typical fuel tank) = 56.78 L
Watch out: UK gallons differ
The imperial gallon is 4.54609 liters — 20% larger. If a British recipe or car spec says "gallons," it's probably imperial.
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