Calculators / Pool volume
Pool Volume Calculator
A 32 × 16 ft pool, 3.5 ft deep at the shallow end and 8 ft at the deep end, holds about 22,023 gallons (83,365 liters). A 24 ft round pool with 4.5 ft of water holds about 15,228 gallons. Enter your pool below.
How many gallons is your pool?
Average depth 5.75 ft. Water weighs about 8.3 lb per gallon: 92 tons in all.
How to calculate pool volume
Find the volume in cubic feet, then multiply by 7.48 to get U.S. gallons. Use the average depth: (shallow end + deep end) ÷ 2.
- Rectangle: length × width × average depth. 32 × 16 × 5.75 ft = 2,944 cu ft = 22,023 gallons.
- Round: 3.1416 × (diameter ÷ 2)² × depth. A 24 ft pool with 4.5 ft of water: 2,036 cu ft = 15,228 gallons.
- Oval: 3.1416 × (length ÷ 2) × (width ÷ 2) × average depth.
- Kidney: 0.45 × (width at the wide end + width at the narrow end) × length × average depth, an approximation used by pool retailers (Leslie's).
Gallons in round above-ground pools
| Diameter | 4 ft of water | 4.5 ft of water |
|---|---|---|
| 12 ft | 3,384 | 3,807 |
| 15 ft | 5,288 | 5,949 |
| 18 ft | 7,614 | 8,566 |
| 21 ft | 10,364 | 11,659 |
| 24 ft | 13,536 | 15,228 |
| 27 ft | 17,132 | 19,274 |
| 30 ft | 21,151 | 23,795 |
Gallons in rectangular in-ground pools
| Size | 3.5 to 6 ft deep | 3.5 to 8 ft deep |
|---|---|---|
| 12 × 24 ft | 10,233 | 12,388 |
| 14 × 28 ft | 13,929 | 16,861 |
| 15 × 30 ft | 15,990 | 19,356 |
| 16 × 32 ft | 18,193 | 22,023 |
| 18 × 36 ft | 23,025 | 27,872 |
| 20 × 40 ft | 28,426 | 34,410 |
Assumes straight walls and a floor that slopes evenly. Rounded corners, steps and benches hold a little less water.
Common questions
How many gallons are in a 24 ft round pool?
With 4 ft of water, about 13,536 gallons. With 4.5 ft, about 15,228 gallons.
Should I use the wall height or the water depth?
The water depth. Above-ground pools are not filled to the top of the wall, so measure from the floor to the water line.
How accurate is the result?
The formulas are exact for straight walls and an evenly sloped floor. Real pools have rounded corners, steps and a deeper hopper, so treat the result as an estimate. It is close enough to size chemicals, then adjust based on water tests.
How long does it take to fill a pool?
Hours = gallons ÷ hose flow (gallons per minute) ÷ 60. Time how long your hose takes to fill a 5-gallon bucket and enter it above. For example, at 10 gallons per minute a 15,228-gallon pool takes about 25 hours.
Why do I need to know my pool's volume?
Pool chemical labels give doses per gallons of water, and pumps and filters are sized by volume. Knowing your gallons helps you avoid adding too much or too little.
How we calculated this
Volumes use standard geometry and the exact conversions 1 cu ft = 7.48052 U.S. gallons = 28.3168 liters. The kidney formula is an approximation published by Leslie's. We test the calculator against 155 worked examples, checked with a separate program. Sources.
Changelog
- : Published.
- : Formulas checked against 155 worked examples, verified with a separate program.
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