Pool Water Volume by Shape
Pool gallonage, the input every pool dose and heater calculation needs.
Example
You enter
- Pool shape rectangle
- Length (ft) 32
- Width (ft) 16
- Shallow-end depth (ft) 3
- Deep-end depth (ft) 8
You get
- Surface area 512 ft^2
- Average depth 5.5 ft
- Pool volume 21065.1
Checked against published worked examples from: NSPF CPO pool-volume method / plane geometry.
Details, formula, and sources
Scopegallons = surface area x average depth x 7.48052, average depth = (shallow + deep)/2. Rectangle area L x W, round pi(D/2)^2, oval (pi/4)L x W. A 32 x 16 ft rectangle 3 to 8 ft deep is 512 ft^2 x 5.5 ft = 2,816 ft^3 = 21,065 gal. A field estimate; a metered fill or plan takeoff is more exact.
Formula or tablegallons = surface_area x avg_depth x 7.48052 gal/ft^3; avg_depth = (shallow + deep)/2. Rectangle area = L x W; round = pi (D/2)^2; oval = (pi/4) L x W.
Source and editionFirst-principles geometry with the 7.48052 gal/ft^3 conversion; the pool-volume method per the NSPF CPO Handbook (by name).
Free accessThe area formulas and the gal/ft^3 conversion are public; CPO course materials proprietary.
What governsEstimate. AHJ and licensed professional govern.
API field namesshape, length_ft, width_ft, shallow_ft, deep_ft, area_ft2, avg_depth_ft, gallons
- Conversion 7.48052 gal per cubic footUS customary
- Average depth (shallow + deep)/2 for a linearly sloping floorNSPF CPO pool-volume method
- Shape area rectangle L x W; round pi (D/2)^2; oval (pi/4) L x Wplane geometry