PoolCare Tools

Pool volume calculator

Enter your pool's dimensions to get its water volume in US gallons, litres and cubic feet. Every other pool calculation — salt, chlorine, pH, alkalinity — starts from this number.

Your pool holds approximately 5,984 US gallons

5,984 US gal · 22,653 L · 800.0 ft³ · average depth 4.00 ft

Formula: length × width × avg depth × 7.48052 (ft³ → US gal)

Use this volume in every other calculation — salt, chlorine, pH and alkalinity all scale with gallons. Measure water depth, not wall height, and allow for a waterline below the coping.

Use 5,984 US gallons in the salt calculator →

How to measure your pool

  1. Measure water depth, not the wall height. The water line normally sits below the coping.
  2. For a pool with a deep end, measure the shallow end and the deep end separately — the calculator averages them.
  3. For an irregular pool, use the "kidney / freeform" shape and enter the actual water-surface area — the area of the water itself, not the rectangle drawn around the pool. If you only have the surrounding rectangle, the calculator's note explains how to discount it.
  4. Round volume is sensitive to the diameter: at 4 ft of water, a 1 ft error moves a 24 ft pool by about 1,130 gallons.

Formula used

rectangular: length × width × average depth × 7.48052
round: π × (diameter ÷ 2)² × average depth × 7.48052
oval: π × (length ÷ 2) × (width ÷ 2) × average depth × 7.48052
kidney / freeform: water surface area × average depth × 7.48052

In metres the same formulas run in cubic metres and the result is converted at 1 m³ = 1,000 litres, with 1 ft = 0.3048 m exact. Switching the units box converts the numbers you type — it does not just relabel them.

7.48052 is the number of US gallons in a cubic foot (1 ft³ = 1728 in³, 1 US gal = 231 in³). All constants and sources →

Next step

Once you know your volume, you can work out how much salt or stabiliser to add. Those calculators apply published dosing formulas and show the source with the result.

This page needs no professional review. It is pure geometry and unit conversion. Pages that recommend a chemical dose are published only after review by a credentialed pool professional.

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