Pool Volume Calculator

1Select your pool shape
Rectangular
L-Shaped
Circle
Triangular
Kidney
Oval
Oblong
2Select your pool type
Above Ground
In-Ground
3Enter pool dimensions
📊 Pool Volume

💊 Shock Treatment Recommendation

💧 Estimated Water Cost (Initial Fill)

Pool Volume Formulas

Rectangular (Constant Depth)

Volume (gal) = L × W × D × 7.5
L = Length (ft), W = Width (ft), D = Depth (ft)
1 ft³ = 7.5 US gallons

Rectangular (Variable Depth)

Volume (gal) = L × W × Davg × 7.5
Davg = (Deep End + Shallow End) / 2
If slope is gradual and even

Circular

Volume (gal) = π × r² × Davg × 7.5
r = Radius (ft) = Diameter / 2
π ≈ 3.14

Triangular (Right Angle)

Volume (gal) = (Base × Height) / 2 × Davg × 7.5
Base & Height in ft; area of right triangle = ½ × base × height

Oval

Volume (gal) = π × (L/2) × (W/2) × Davg × 7.5
L = Overall length, W = Overall width
(Ellipse area)

Kidney

Volume (gal) = 0.45 × (A + B) × L × Davg × 7.5
A, B = lengths of the two lobes (ft)
L = overall length (ft)
Based on industry standard approximation
Quick Reference
  • 1 cubic foot (ft³) = 7.48 US gallons
  • 1 ft³ = 6.23 UK gallons
  • 1 ft³ = 28.32 liters
  • 1 m³ = 1000 liters
  • 1 gallon of water ≈ 8.33 lbs
  • 1 inch = 0.0833 ft

Pool Volume Calculator FAQs

How does the pool volume calculator work?

Simply follow the four steps: select your pool shape, choose the installation type (above ground or in‑ground), enter the required measurements, and click Calculate Volume. The tool automatically applies the correct geometric formula for your shape and displays the volume in your preferred output unit.

Can I switch between imperial and metric units?

Yes! You can toggle input units between feet and meters before entering dimensions. The output can be displayed in US gallons, UK gallons, liters, or cubic meters – just use the toggle above the results.

Why are some pool types disabled for certain shapes?

This reflects typical real‑world designs. Circular pools are almost always above‑ground (e.g. frame or inflatable pools). Triangular and kidney‑shaped pools are predominantly built in‑ground due to their complex perimeters. The calculator restricts the type to match these common configurations, ensuring realistic volume estimates.

How accurate are the volume calculations?

The calculator uses standard geometric formulas for rectangular, circular, triangular, and oval shapes – these are mathematically exact. For kidney pools we apply an industry‑accepted approximation (0.68 × length × width × average depth). Results are suitable for chemical dosing and fill‑cost estimates, but exact volume may vary slightly with pool curvature.

How reliable are the water cost estimates?

The estimates are based on 2026 average municipal water rates for the US, Canada, and Australia. Actual costs depend on your local utility provider, drought surcharges, and whether you use a garden hose or a water delivery service. Use these figures as a practical guide — always check with your local supplier for exact rates.

What is the recommended shock treatment amount?

We suggest approximately 1 lb of shock (calcium hypochlorite) per 10,000 US gallons per weekly treatment. The calculator shows the corresponding weight in pounds and kilograms. Always follow the specific instructions on your shock product, and adjust based on water conditions and bather load.

Can I use this calculator for any pool shape?

It covers the five most common shapes: rectangular, circular, triangular, kidney, and oval. If you have a freeform or highly irregular pool, you can approximate it with the kidney or oval option for a reasonable estimate. For precise chemical dosing, we recommend consulting a pool professional.