How many pounds is 4.5 gallons?
How many pounds is 4.5 gallons?
Answer
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 4.5 gallons runs from 19.1 lbs (propane) to 38.7 lbs (milk).
In imperial (UK) gallons of 4.54609 L instead of 3.785411784 L, 4.5 UK gallons of water would weigh 45 lbs.
How the weight of 4.5 gallons of water was worked out
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.
4.5 gal × 0.998 kg/L × 3.785411784 ÷ 0.45359237
≈37.5 lbs
(thirty-seven point five 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 4.5 gallons weighs 37.5 lbs here, and one pound of it fills 0.12 gallons there.
Related Calculations
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
<a href="https://calculat.io/en/volume/gal-to-lbs/4.5--all-substances">4.5 gallons to pounds — 37.5 lbs of water - Calculatio</a>
How much 4.5 gallons of each substance weighs
| Substance | Weight of 4.5 gallons | One US gallon | Density, kg/L |
|---|---|---|---|
| Diesel | 31.3 lbs | 6.96 lbs | 0.834 |
| Gasoline | 27.8 lbs | 6.18 lbs | 0.74 |
| Milk | 38.7 lbs | 8.6 lbs | 1.03 |
| Propane | 19.1 lbs | 4.24 lbs | 0.5076 |
| Vegetable oil | 34.5 lbs | 7.68 lbs | 0.92 |
| Water | 37.5 lbs | 8.33 lbs | 0.998 |