Loam & Level

Pool volume calculator

Choose your pool's shape and enter its size and depth. You'll get the gallons, which you need for chemical dosing, heater sizing and filling.

LengthWidthTop viewShallowDeepSide view, depth to the water line
Measure depth from the water line, not the top edge of the pool.
–gallons
Liters
–
Average depth (ft)
–
Surface area (sq ft)
–

For a pool with one depth, enter the same number in both depth fields.

How the math works

Average the shallow and deep end depths, then multiply by the surface area and by 7.48 gallons per cubic foot. A 32 by 16 foot rectangular pool, 3.5 feet at the shallow end and 8 feet at the deep end, averages 5.75 feet deep and holds about 22,000 gallons.

Round and oval pools use the area of a circle or ellipse instead of a rectangle. An above-ground round pool 24 feet across with 4 feet of water holds about 13,500 gallons.

Why pool volume matters

Chlorine, shock, pH adjusters and other chemicals are dosed by gallons, so an accurate volume keeps the water balanced without wasting product. Heaters, pumps and filters are also sized by volume.

Common questions

Should I measure to the top of the pool or the water line?

Measure depth to the water line, not the top edge. Water usually sits a few inches below the coping or top rail.

What about a pool with a gradual slope?

Averaging the shallow and deep end works well for a steady slope. A pool with a long flat shallow area and a short deep hopper holds less than the average suggests, so treat the result as an upper estimate.

How long will it take to fill?

A garden hose delivers roughly 5 to 10 gallons per minute. At 8 gallons per minute, a 20,000 gallon pool takes about 42 hours.

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