Pool Volume Calculator
Work out the volume of a swimming pool in litres or gallons from its dimensions.
How much water a pool holds
Knowing a pool's volume is the starting point for looking after it — the water it holds determines how much chemical to add, how long it takes to heat, and how a pump is sized. This works out the volume from the pool's dimensions and shape, so you have the figure the rest of pool care depends on.
Enter the pool's dimensions to see its volume.
Shape and average depth
The calculation depends on the shape — a rectangular pool is straightforward, while round, oval or irregular pools need their own formulas. The factor most often fumbled is depth: many pools slope from a shallow to a deep end, so you use the average depth, not one or the other, or the volume comes out well off. Getting the volume right genuinely matters for chemical dosing, where too much or too little is thrown off by a wrong volume.
Frequently asked questions
What if my pool has a shallow and a deep end?
Use the average depth between them, not one end, or the volume — and any chemical dosing based on it — will be off.
Why does pool volume matter?
It sets how much chemical to add, how long the water takes to heat, and how the pump is sized, so accuracy affects real pool care.
Is anything uploaded?
No. The calculation happens in your browser.