# How Much Does A Gallon Of Water Weigh?

How Much Does A Gallon Of Water Weigh? Like solid and gas, the capacity of a liquid can easily be determined using a unit of measurement known as a gallon. A gallon measures a unit capacity of liquid in both the US customary units and the British imperial system. There are three different sizes of gallons in use today, namely the imperial gallon used in the UK, Canada, and some Caribbean countries.

The US gallon used mainly in the US and some Latin American countries, and the US dry gallon which is the least used of the three. The three sizes of measurements are significantly different with an imperial gallon defined as 4.546 liters, US gallon as 3.785 liters, while US dry gallon is defined as 4.405 liters.

## A Gallon of Water

How much does a gallon of water weigh? This is one of the questions that is widely dodged or inaccurately answered by many. Some people have estimated the answer to this question to be between 5 and 15 pounds. Some people trying to be smart have treated it as a tricky question without an exact answer. Other people will go as far as asking the temperature of the water. Initially, the weight of water was defined as 1 kg/liter. However, the definition was discarded since the density of water is affected by changes in temperatures and atmospheric pressure. The answer is simple; a gallon of water weighs about 8.3 pounds. The imperial gallon of water is defined as 10.02 pounds at its maximum density while the weight of US dry gallon of water is defined as 9.71 pounds. However, the answer comes with a caveat. The weight per gallon of water fluctuates with temperature.

## Effects of Water Temperature on Weight

Temperature is one of the ways to measure the amount of energy in water. A higher temperature means higher energy and vice versa. Higher water energy causes water molecules to vibrate, pushing their neighbors to the side. Thus, the density of water decreases with the increase in the energy of water. Since a gallon is a set amount of space, the number of water molecules in that space will fluctuate with the changing energy levels. So, a gallon of warm water weighs slightly less than a gallon of cold water with the difference depending on the temperatures in question. For instance, at 500 Fahrenheit, a gallon of water would weigh approximately 8.3 pounds while at 2000 Fahrenheit a gallon of the same water would weigh 8.03 pounds. However, the value of water remains the same despite the temperature changes since the temperature does not affect the composition of water.

**Question: How much does a gallon of water weigh?**

**Answer**: A US gallon of water weighs 8.34 lbs or 3.78 kg at 62 °F (17 °C). An imperial gallon (UK) weighs 10.022 lbs or 4.546 kg, at its most dense temperature, which is 2.20456 lbs / L at 4 °C or 39 °F.

## How Much Does A Gallon Of Water Weigh In Pounds?

**Answer and Explanation:**

**8.34 pounds**(lb) or 3.785 kilograms (kg) at room temperature.

## How Much Does A 5 Gallon Jug Of Water Weigh?

**8.34 pounds**-mass of water, so a US five-gallon bottle of water weighs

**41.7 pounds**-force plus the weight of the bottle. Dec 15, 2017

It depends on which type of gallon you mean, US gallon or UK Imperial Gallon. So, it must be 2 answers to this question.

There are 4.54609 liters in a UK gallon and 3.785 liters in a US gallon. A liter of water equal to 2.204684 pounds or 1.000028 kilograms

Therefore, UK gallon of water weigh are:

4.54609 x 2.204684 = 10.0227 pounds, or

4.54609 x 1.000028 = 4.5462 kilograms

And US gallon of water weighs are

3.785 x 2.204684 = 8.3447 pounds, or

3.785 x 1.000028 = 3.7851 kilograms

5 UK gallons of water weigh are

5 x 10.0227 pounds = 50.1335 pounds

5 x 4.5462 kilograms = 22.731 kilograms

5 US gallons of water weigh are

5 x 8.3447 pounds = 41.7235 pounds

5 x 3.7851 kilograms = 18.9255 kilograms

Final Answer

5 UK gallons water weigh are 50.1335 pounds or 22.731 kilograms

5 US gallons water weigh are 41.7235 pounds or 18.9255 kilograms

**Ballpark Calculation (for all temperatures)**

1 gallon is about 3.75 liters

1 liters = 1 kilogram (density of water is 1 kg/liter)

1 kg is about 2.2 lbs

so, 3.75 kg is about 8.25 lbs and 1 gallon is about 8.25 lbs

### Three Different Units of Gallon

It makes a difference which unit of **gallon** you are using. There are two US definitions of a gallon. The US liquid gallon (most commonly used) is defined as 231 cubic inches, which is 3.785 liters, and weighs 8.344 lbs at its highest density.

The US dry gallon is defined as 1/8th of a US bushel, which is 268.8025 cubic inches or 4.405 L. The weight of a US dry gallon is 9.711 lbs of water at its highest density.

The UK gallon or imperial gallon originally was defined as 10 lbs of water, but the modern definition is exactly 4.54609 L or 10.02 lbs of water at its maximum density.

### Easy Way To Remember the Weight of Water

While you’ll want to keep the exact volume definitions in mind for scientific calculations, for everyday use you can remember the weight of water using the simple rhyme: A pint’s a pound, the world around.

The saying refers to the rough equivalence between 16 fluid ounces (a pint) and 16 ounces avoirdupois weight. A gallon is 4 quarts or 8 pints, so a gallon weighs approximately 8 lbs.