How many pounds is 55 gallons?

"Gallons to Pounds" Calculator
How many pounds in
gal

How many pounds is 55 gallons?

Answer

55 US gallons of water weighs
458.1 lbs

The question names no substance, so the answer above is for water — the usual reference, taken at 20 °C (68 °F). Other liquids weigh differently at the same volume: across the table below 55 gallons runs from 233 lbs (propane) to 472.8 lbs (milk).

In imperial (UK) gallons of 4.54609 L instead of 3.785411784 L, 55 UK gallons of water would weigh 550.1 lbs.

How the weight of 55 gallons of water was worked out

pounds = gallons × density (kg/L) × 3.785411784 ÷ 0.45359237

A US gallon is exactly 3.785411784 liters and a pound is exactly 0.45359237 kilograms, so the density in kilograms per liter turns into pounds per gallon by multiplying by the first and dividing by the second.

55 gal × 0.998 kg/L × 3.785411784 ÷ 0.45359237

≈

458.1 lbs

(four hundred fifty-eight point one lbs)

The density comes from FAO/INFOODS Density Database v2.0: liquid water at 20 °C; rounding to 1.00 kg/L is fine for everyday use.

Why the same gallon weighs differently

A gallon measures volume, a pound measures weight, and density is what ties them together: how many pounds one US gallon of this particular substance comes to. Water is the everyday reference at 8.33 lbs per gallon, and everything else sits above or below it.

Across this page the spread is wide: one US gallon of propane weighs 4.24 lbs, one US gallon of milk 8.6 lbs — at the very same volume.

The other way round: how many gallons a weight fills

This page starts from a volume and answers in pounds. The opposite question — how many gallons a given weight comes to — is what the pounds to gallons calculator is for, and in metric units the same question is kilograms to liters. All of them read one density table, so their numbers agree.

For water that means 55 gallons weighs 458.1 lbs here, and one pound of it fills 0.12 gallons there.

See Also

  • Pounds to Gallons - How many gallons a pound of water, milk, oil or propane takes — by density
  • Liters to Pounds - How much a liter of water, gasoline or propane weighs in pounds — by density
  • Liters to Kilograms - How many kilograms are in a liter of water, honey, gasoline, sand and other substances — by density
  • Gallons to Liters - Convert US Gallons to Liters
  • Lbs to Kg - Convert Pounds to Kilograms

About "Gallons to Pounds" Calculator

This calculator converts US gallons to pounds through the density of the substance: weight equals volume times density. A gallon on its own has no weight — a gallon of water weighs 8.33 lbs, a gallon of gasoline 6.18 lbs and a gallon of propane only 4.24 lbs. When no substance is named, the answer is for water, and the table shows every other liquid next to it. For example, it can help you find out how many pounds is 55 gallons? (The answer is: 458.1). The gallon here is the US liquid gallon of 231 cubic inches; the imperial gallon used in the UK is a fifth larger, and every result page names what the same number of imperial gallons would weigh.
"Gallons to Pounds" Calculator
How many pounds in
gal

How much 55 gallons of each substance weighs

SubstanceWeight of 55 gallonsOne US gallonDensity, kg/L
Diesel382.8 lbs6.96 lbs0.834
Gasoline339.7 lbs6.18 lbs0.74
Milk472.8 lbs8.6 lbs1.03
Propane233 lbs4.24 lbs0.5076
Vegetable oil422.3 lbs7.68 lbs0.92
Water458.1 lbs8.33 lbs0.998

FAQ

How many pounds is 55 gallons?

55 US gallons of water weighs 458.1 lbs

Why is the answer given for water?

Because the question names no substance, and water is what people mean by default: 55 US gallons of water weighs 458.1 lbs at 20 °C (68 °F). A gallon measures volume, not weight, so every other liquid gives its own number — the table on this page lists them side by side.

What is the heaviest and the lightest at this volume?

The lightest in the table is propane at 233 lbs, the heaviest is milk at 472.8 lbs. The volume is identical; only the density differs.

How do you convert 55 gallons to pounds for another liquid?

Multiply by the weight of one US gallon of that liquid. If you know its density in kilograms per liter, one US gallon weighs about density × 8.3454 lbs, because a US gallon is exactly 3.785411784 liters and a pound is exactly 0.45359237 kilograms.