Pool Volume Calculator

Average depth is the arithmetic mean of the shallow-end and deep-end depths — add the two together and divide by two. For a pool that slopes gradually from 3 feet at the shallow end to 8 feet at the deep end, the average depth to enter is 5.5 feet, not either endpoint alone. If the pool has a long flat shallow section before the slope begins (common in family pools), a rough weighted estimate that leans toward the shallow-end depth will be more accurate than a simple midpoint average, since more of the pool's footprint sits at the shallower depth.

The calculator only uses whichever dimension applies to the shape you selected — diameter for round pools, length and width for rectangular and oval pools. Selecting Round hides the Length and Width fields and shows Diameter instead, and switching back to Rectangle or Oval reverses that, so you only ever see the fields that actually affect your result.

The fill-time estimate assumes a typical garden hose delivers about 9 gallons per minute, which is a reasonable midpoint for a standard 5/8-inch hose at normal residential water pressure, but real flow rates commonly range from roughly 6 to 12+ gallons per minute depending on hose diameter, length, and your home's actual water pressure. Treat the fill-time figure as a rough planning number — if you need a precise fill schedule, time your own hose filling a 5-gallon bucket and scale the result using your measured rate instead.

Gallons is the unit pool professionals and chemical dosing instructions use — chlorine, algaecide, and pH adjuster dosing charts are almost universally written per thousand gallons — while cubic feet is the more natural unit for construction and excavation calculations, such as estimating how much soil needs to be removed to build the pool. Having both readily available means you can move directly from this calculator to a pool chemical dosing calculator without doing your own unit conversion.