Unlike a simple box, most swimming pools have sloped floors that go from shallow to deep. Because of this, calculating the water volume requires finding an Average Depth before multiplying by the overall surface area.

Tips for Accuracy

• Measure at the water line: Don't measure to the top of the pool wall. Measure from where the water actually rests.
• Free-form pools: Calculate the average width, multiple by the length, by the average depth, and use the 7.5 multiplier. Try mapping it out into smaller squares if necessary.
• Flat bottoms: Simply use your flat depth for both the shallow and deep inputs!