Pool Volume Calculator
Calculate how many gallons or liters your swimming pool holds. Select your pool shape, enter dimensions, and get volume plus chemical dosing estimates.
Pool Volume Calculator
Frequently Asked Questions
How many gallons is my pool?
For rectangular pools: Length × Width × Average Depth × 7.48 = gallons. For round pools: Diameter² × 0.785 × Depth × 7.48. Use the calculator above for exact results.
How do I calculate average pool depth?
Add the shallow end depth and deep end depth, then divide by 2. Example: 3 ft (0.9 m) shallow + 8 ft (2.4 m) deep = 11 ft ÷ 2 = 5.5 ft (1.7 m) average depth.
How much salt for a saltwater pool?
About 40 lbs per 2,000 gallons (18 kg per 7,570 L) to reach the typical 3,200 ppm salinity target. A 15,000-gallon (57,000 L) pool needs approximately 300 lbs (136 kg) of pool salt for initial setup.
How many gallons is a standard 15×30 pool?
A 15×30 ft rectangular pool with 5 ft average depth holds approximately 16,831 gallons (63,720 liters). Formula: 15 × 30 × 5 × 7.48 = 16,831.
Common Pool Sizes and Volumes
| Pool Size (ft / m) | Shape | Avg Depth | Gallons | Liters |
|---|---|---|---|---|
| 12 × 24 ft (3.7 × 7.3 m) | Rectangle | 5 ft (1.5 m) | 10,778 | 40,800 |
| 15 × 30 ft (4.6 × 9.1 m) | Rectangle | 5 ft (1.5 m) | 16,831 | 63,720 |
| 16 × 32 ft (4.9 × 9.8 m) | Rectangle | 5.5 ft (1.7 m) | 21,067 | 79,730 |
| 18 × 36 ft (5.5 × 11 m) | Rectangle | 5.5 ft (1.7 m) | 26,653 | 100,890 |
| 20 × 40 ft (6.1 × 12.2 m) | Rectangle | 5.5 ft (1.7 m) | 32,914 | 124,590 |
| 15 ft (4.6 m) round | Circle | 4 ft (1.2 m) | 5,288 | 20,020 |
| 18 ft (5.5 m) round | Circle | 4 ft (1.2 m) | 7,614 | 28,820 |
| 24 ft (7.3 m) round | Circle | 4 ft (1.2 m) | 13,536 | 51,240 |
| 12 × 24 ft (3.7 × 7.3 m) | Oval | 4 ft (1.2 m) | 6,773 | 25,640 |
Why Pool Volume Matters
- Chemical dosing — chlorine, pH adjusters, and algaecide are all dosed per gallon
- Pump sizing — your pump should turn over the full pool volume in 8–12 hours
- Heater selection — BTU output must match pool size for efficient heating
- Salt systems — salt chlorine generators are rated by pool volume
Related Calculators
- Concrete Calculator — for pool decks, walls, and patios
- Tile Calculator — tiling the pool walls or surround?
- Cubic Yards Calculator — generic volume calculator
- Paver Calculator — pool deck paving
- 3D Volume Calculator — volume for non-rectangular pool shapes
- Voltage Drop Calculator — wiring voltage drop for pool pumps and lights
- All Construction Calculators
1 cubic foot = 7.48052 US gallons. 1 US gallon = 3.78541 liters. Chemical amounts are approximate guidelines — always test before treating.
