Pool Volume Calculator

Why Calculate Pool Volume?

Knowing your pool's exact water volume is essential for: accurate chemical dosing (chlorine, pH adjusters), filter sizing, heater selection, water change planning, and filling time estimation.

Volume Formulas by Pool Shape

Rectangular: V = Length × Width × Average Depth

Circular: V = π × r² × Depth = π × (Diameter/2)² × Depth

Oval: V = π × (Length/2) × (Width/2) × Depth

L-shaped: Split into two rectangles, calculate separately, and add.

Variable depth (deep end + shallow end): Average depth = (shallow + deep) / 2. This gives a close approximation.

Volume in litres = Volume in m³ × 1,000

Practical Examples

Example 1 — Rectangular pool: 10m × 5m, shallow end 1.2m, deep end 2.0m. Average depth = 1.6m. V = 10 × 5 × 1.6 = 80 m³ = 80,000 litres.

Example 2 — Round pool: Diameter 6m, depth 1.5m. V = π × 3² × 1.5 = 42.4 m³ = 42,400 litres.

Chemical Dosing Guide

• Chlorine shock: ~170g of 70% granular per 50,000L to raise free chlorine by ~5 ppm.
• pH down (muriatic acid): ~0.5L per 50,000L to lower pH by 0.2.
• Always test first; calculate dose from volume × required change.