Water Weight Hub

1 Gallon Water Weight Calculator

Find how much one gallon of water weighs in pounds, kilograms, and ounces. Compare US liquid gallons, imperial gallons, freshwater, and saltwater estimates.

Calculate 1 gallon water weight

Water weight result
Pounds
Kilograms
Ounces
US tons
Liters equivalent
Total load with container
This is an estimate for planning. For structural, trailer, deck, floor, or lifting safety, include the container and equipment weight and consult a qualified professional when needed.

1 Gallon Water Weight quick answers

1 US gallon of waterAbout 8.34 lb / 3.79 kg

This is the common everyday answer for fresh water.

1 imperial gallon of waterAbout 10.02 lb / 4.55 kg

An imperial gallon is larger than a US liquid gallon.

1 gallon of saltwaterAbout 8.55 lb / 3.88 kg

Saltwater is slightly denser than freshwater.

FormulaPounds ≈ gallons × 8.34

For one US gallon, the calculation is 1 × 8.34.

1 Gallon Water Weight conversion table

Use this table for fast water-only estimates. Add container, tank, stand, trailer, or packaging weight separately.

VolumePoundsKilogramsTypical use
1 US gallon8.34 lb3.79 kgOne gallon jug
2 US gallons16.68 lb7.57 kgTwo jugs
3 US gallons25.02 lb11.36 kgSmall container
4 US gallons33.36 lb15.14 kgContainer load
5 US gallons41.70 lb18.93 kgBucket / cooler bottle
10 US gallons83.40 lb37.85 kgLarge container

When this water weight matters

One-gallon water bottles and jugs

One US gallon of fresh water weighs about 8.34 pounds, or about 3.79 kilograms. A full one-gallon jug weighs more after adding the plastic container and cap.

Cooking, camping, and emergency storage

One gallon is a useful planning unit for drinking water, camping water, cleaning water, and emergency storage. Multiply the number of gallons by 8.34 to estimate water-only weight.

US gallon vs imperial gallon

A US liquid gallon weighs about 8.34 pounds of fresh water. An imperial gallon is larger and weighs about 10 pounds of water.

Fresh water formula: pounds ≈ US gallons × 8.34

Saltwater estimate: use roughly 2.5% more than freshwater for everyday planning.

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1 Gallon Water Weight FAQ

How much does 1 gallon of water weigh?

One US gallon of fresh water weighs about 8.34 pounds, or about 3.79 kilograms. A full one-gallon jug weighs more after adding the plastic container and cap.

Does saltwater weigh more?

Yes. Saltwater is denser than freshwater, so the same volume weighs slightly more. The calculator includes a simple saltwater estimate for planning.

Should I include the container weight?

Yes. If you are planning a tank, bucket, cooler bottle, pool, trailer, or storage system, add the empty container and equipment weight to the water-only weight.