Construction & Materials

Pool Volume & Gallons Calculator

Calculate pool water volume in gallons for rectangular, round, oval, and irregular swimming pools.

Reviewed by Elena Rostova, P.E. (P.E., M.S. Civil Engineering (Georgia Tech))

Verified for accuracy•Updated 2026

Interactive Calculator

1. Provide Details

Pool Shape

Length or Diameter (ft)

Width (ft - if Rect/Oval)

Shallow End Depth (ft)

Deep End Depth (ft)

2. Output Results

Average Pool Depth5.5 ft

Volume in Cubic Feet2,816 cu ft

Total Pool Volume21,064 US Gal

How to Calculate: Formula & Steps

Uses geometric volume formulas multiplied by 7.48 gallons per cubic foot (with shape adjustment coefficients).

Formula Used:Gallons = Length × Width × Avg Depth × Multiplier (7.5 for Rect, 5.9 for Circular, 6.7 for Oval)

Step-by-Step Calculation Example

A 16ft × 32ft rectangular pool with a shallow depth of 3ft and deep depth of 8ft (avg depth 5.5ft) holds ~21,120 gallons of water.

Common Mistakes to Avoid

Using maximum deep end depth instead of calculating average depth across the pool floor slope.

Practical Use Cases

Sizing pool pumps, filters, and heaters
Accurate chemical dosing for shock and chlorine treatments

Expert Tips

Always calculate average depth as (Shallow Depth + Deep Depth) / 2 for slope-bottom pools.

Disclaimer

This calculation tool is provided for educational and informational estimation purposes only. Results are based on mathematical formulas and user-supplied parameters. They do not constitute formal underwriting, financial, tax, engineering, or legal determinations.