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Gallons to Pounds Calculator

Convert US gallons to pounds for water and other common liquids. A gallon of water weighs about 8.34 pounds, but a gallon of honey weighs around 12 pounds because it is denser. Select your liquid from the list to get an accurate weight estimate.

Converting between volume (gallons) and weight (pounds) requires knowing the liquid's density. This is not a fixed ratio because different liquids have different densities.

Liquid Weights (Pounds per US Gallon at Room Temperature):

Liquid lb/gal kg/L
Water 8.345 1.000
Whole Milk 8.6 1.030
Gasoline 6.3 0.755
Diesel Fuel 7.1 0.850
Honey 12.0 1.438
Olive Oil 7.6 0.911
Maple Syrup 11.0 1.318
Beer 8.4 1.007
Seawater 8.6 1.025

The classic question: "How much does a gallon of water weigh?" The answer is 8.345 pounds (3.785 kg) at 62°F (16.7°C). Temperature matters slightly. Hot water is slightly lighter because it expands; cold water is slightly heavier.

Practical examples: A 5-gallon water jug weighs about 41.7 lb. A full 55-gallon drum of water weighs about 459 lb. If you are loading liquids into a truck, knowing the weight per gallon helps you avoid exceeding axle limits.

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