Pool Volume Calculator
Calculate a swimming pool’s volume in gallons, litres, and cubic feet for rectangular, round, or oval pools from the dimensions and average depth. Calculates in your browser.
Pool volume
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Show the math
Volume is the surface area times the average depth, in gallons:
rectangle = length × width × depth × 7.48
round = π × (diameter ÷ 2)² × depth × 7.48
Use the average depth (shallow end plus deep end, divided by two). Knowing the gallons is the first step for dosing chemicals, always follow the product label. All math runs locally in your browser.
What this does
A pool volume calculator finds a swimming pool’s volume in gallons, litres, and cubic feet for rectangular, round, or oval pools from the dimensions and average depth.
How to use it
- Choose the pool shape.
- Enter the dimensions.
- Enter the average depth.
- Read the gallons and litres.
How it works
Average depth is the shallow and deep ends added and halved. Each cubic foot holds about 7.48 gallons.
gallons = surface area × avg depth (ft) × 7.48
Understanding your result
Volume is the number every chemical dose depends on, so an accurate average depth matters: add the shallow and deep ends and halve them. Dosing against a wrong volume is the usual cause of cloudy or over-treated water, so keep this figure handy whenever you balance the pool.
Example
A 16×32 ft rectangular pool at 5 ft average depth holds about 19,000 gallons.
Sources & methodology
Last updated .
Frequently asked questions
What depth should I enter?
Use the average depth (add the shallow and deep ends and divide by two) so the volume reflects the whole pool.
Why do I need the gallons?
Pool volume sets the dose for every chemical and the run time for filtration, so it is the starting point for water care.
How accurate is it?
It is exact for true rectangles, circles, and ovals; irregular or freeform pools are an estimate, so round up a little.
Is anything stored?
No. Everything is calculated locally in your browser.
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