Skip to main content
Calculator Answers

Pool Volume Calculator

Blake Boege
Written by Blake Boege · Founder, Calculator Answers

A pool volume calculator is a home maintenance utility that computes the liquid capacity of a swimming pool. The calculator supports common pool shapes, including rectangular, oval, circular, and custom freeform configurations, factoring in shallow and deep end measurements to estimate average depth. By applying standard volumetric equations, it calculates total volume in cubic feet, gallons, or liters. Pool owners, technicians, and contractors use this tool to determine correct chemical dosing, heating requirements, and filling costs.

Pick the pool shape, enter the dimensions and depths, and the calculator returns the volume in cubic feet, gallons, and liters. Use the shallow and deep depths separately for sloped pools.

Quick Answer

Calculate your swimming pool's volume in gallons or liters. Enter the pool shape, dimensions, and depth to determine its capacity.

Pool shape

ft
ft
ft
ft

For a flat-bottom pool, set this equal to the shallow depth.

Assumptions

  • Average depth = (shallow + deep) / 2. Good for linear slopes; pools with hopper bottoms or other complex shapes will need section-by-section math.
  • 1 cubic foot = 7.48052 US gallons = 28.3168 liters.
  • Oval volume uses ellipse area: π x (L/2) x (W/2).
  • Educational estimate. For exact fill or chemical-dose math, consult the pool manufacturer or a pool service.
Pool volume

Pool volume

21,065 gallons

79,740 liters; 2,816 ft³

ShapeRectangular
Footprint512 sq ft
Average depth5.5 ft
Volume2,816 ft³
Gallons21,065 gal
Liters79,740 L

Add about 5 to 10 percent for splash and trim if you are sizing ongoing top-up water. For chemical dosing, follow the product label using the gallons reported above.

Was this helpful?

Examples

Rect 32 x 16 ft, 3 to 8 ft

≈ 13,170 gal

Round 18 ft dia, 4 ft deep

≈ 7,610 gal

Oval 24 x 12 ft, 4 ft flat

≈ 6,765 gal

Rect 20 x 10 ft, 4 ft flat

≈ 5,985 gal

How it works

Volume is the surface area of the pool times the average depth. The calculator picks the right area formula for the shape and averages the shallow and deep depths.

Rectangular · V = L x W x avgDepth

Round · V = π x r² x avgDepth

Oval · V = π x (L/2) x (W/2) x avgDepth

Gallons = V (ft³) x 7.48052. Liters = V (ft³) x 28.3168.

Related volume calculators

Related Calculators

More tools from Home

Cubic Feet CalculatorCalculate volume in cubic feet from any length, width, and height. Supports feet, inches, yards, centimeters, and meters.

Frequently asked questions

Volume equals the pool footprint (the area looking down) times the average water depth. For shallow + deep end pools, the calculator uses the average of the two depths.

Pool chemicals, pumps, heaters, and salt are dosed and sized in gallons (or liters in metric countries). The calculator reports both so you can match the unit your product specifies.

1 cubic foot of water = 7.48052 US gallons = 28.3168 liters. The calculator does these conversions for you, but it can be useful for sanity checking.

Oval pool area uses the ellipse formula: π x (length / 2) x (width / 2), where length and width are the long and short axes of the pool. Combine with the average depth for volume.

Split it into sections, compute each section's volume separately, and add them. The 'average of shallow and deep' approach assumes a linear slope between the two ends; hopper-bottom pools deviate from that.

It gives the gallon count you need to follow chemical product labels. Always follow the label and a balanced-water guide; chemistry is not just volume. This page is an educational estimate, not pool-care advice.