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Pool Volume Calculator
Gallons of water in a rectangular, round, oval or kidney pool — the number every chemical dose depends on.
How it's calculated
Average depth = (shallow + deep) ÷ 2. Volume in cubic feet: rectangle = length × width × depth; round = π × radius² × depth; oval = π × (length ÷ 2) × (width ÷ 2) × depth; kidney ≈ length × width × 0.75 × depth. Gallons = cubic feet × 7.48. For a freeform pool, treat it as two or three rectangles and add them.
Example
A 32 × 16 ft rectangle from 3½ to 6 ft deep: average 4.75 ft, 2,432 ft³ — about 18,190 gallons.
Typical residential pool sizes
| Size | Avg depth | Approx. gallons |
|---|---|---|
| 12 × 24 ft rectangle | 4.5 ft | 9,700 |
| 15 × 30 ft rectangle | 4.5 ft | 15,100 |
| 16 × 32 ft rectangle | 4.75 ft | 18,200 |
| 18 × 36 ft rectangle | 5 ft | 24,200 |
| 24 ft round above-ground | 4 ft | 13,500 |