How to Calculate Your Pool Volume (Step-by-Step)

Why You Need to Know Your Pool Volume

Your pool volume determines how much chemical to add, what size pump/filter/heater you need, and how much water costs. Getting this number right is the foundation of pool maintenance.

Rectangle/Square Pools

Formula: Length × Width × Average Depth × 7.48 = Gallons

Example: 32ft × 16ft × 4.75ft (avg) × 7.48 = 19,213 gallons

Round Pools

Formula: Diameter × Diameter × Average Depth × 5.9 = Gallons

Example: 18ft × 18ft × 4ft × 5.9 = 7,646 gallons

Oval Pools

Formula: Long Diameter × Short Diameter × Average Depth × 5.9 = Gallons

Kidney/Freeform Pools

Formula: Length × Width × Average Depth × 7.48 × 0.45 = Gallons

The 0.45 factor accounts for the irregular shape removing roughly 55% of the rectangular area.

L-Shaped Pools

Break the L into two rectangles, calculate each separately, then add them together.

How to Measure Average Depth

  1. Measure the shallow end depth
  2. Measure the deep end depth
  3. Average = (Shallow + Deep) ÷ 2
  4. For pools with a hopper bottom, measure at the shallow end, the break point, and the deep end

Use our pool volume calculator to do the math instantly.