🏊 Pool Volume Calculator
Pool volume is the surface area times the average depth: rectangular is length × width × depth, and round is π × radius² × depth.
12,680
US gallons
48,000
Litres
48
Cubic metres
Volume uses the average depth — for a pool that slopes from shallow to deep, average the two ends ((shallow + deep) ÷ 2). Knowing the gallons is the basis for dosing chlorine, shock, algaecide and other chemicals correctly. Round pools use the diameter; oval and rectangular use length × width. 🔒 In your browser.
How the pool volume calculator works
Choose the shape and enter the dimensions and average depth (in metres or feet). For a rectangular pool the volume is length × width × depth; for a round pool it's π × (diameter ÷ 2)² × depth; for an oval it's π × (length ÷ 2) × (width ÷ 2) × depth. The result is converted to US gallons, litres and cubic metres.
Use the average depth: for a pool that slopes from a shallow to a deep end, average the two depths ((shallow + deep) ÷ 2). Knowing the exact volume in gallons is the foundation for dosing every pool chemical correctly — chlorine, shock, algaecide, pH adjusters and stabiliser are all specified per volume of water, so an accurate figure keeps your water balanced and avoids over- or under-dosing.
Frequently asked questions
How do I calculate pool volume in gallons?
Multiply the surface area by the average depth to get cubic units, then convert. This tool does it for rectangular, round and oval pools and shows US gallons, litres and cubic metres.
What depth should I use for a sloped pool?
The average depth — add the shallow-end and deep-end depths and divide by two. Using just the deep end overstates the volume; using the shallow end understates it.
Why do I need to know my pool volume?
Because pool chemicals are dosed per volume of water. Chlorine, shock, algaecide and pH adjusters all reference gallons or litres, so an accurate volume is essential for correct, safe dosing.
How do I measure a round or oval pool?
For a round pool, measure the diameter (the full width across the centre). For an oval, measure the longest length and the widest width. Enter those with the average depth.