Dosing pool chemicals correctly — chlorine, pH adjusters, algaecide — depends entirely on knowing your pool's actual water volume, since chemical product instructions are almost always given per gallon or per thousand gallons.
This calculator handles both rectangular and round pool shapes, using the appropriate volume formula for each and converting cubic feet into gallons using the standard 7.48 gallons per cubic foot conversion factor.
For pools with varying depth (like a sloped shallow-to-deep end), using the average of the shallow and deep depths as your "average depth" input gives a reasonably accurate total volume estimate.
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Frequently asked questions
How do I find average depth for a sloped pool?
Add the shallow end depth and deep end depth together and divide by two — this gives a reasonable average depth to use for the volume calculation.
Why convert to gallons instead of just using cubic feet?
Pool chemical dosing instructions are almost universally given in gallons, so converting to that unit makes the volume figure directly usable for calculating chemical amounts.