Calculate swimming pool water volume in gallons. Estimate chemical needs, fill time, and water costs.
Calculate pool water volume and maintenance requirements.
The Swimming Pool Water Calculator helps you accurately determine your pool's water volume, essential for proper chemical dosing, heating costs, and fill time estimates. Whether you're a new pool owner or managing maintenance, knowing your exact water volume is critical.
According to the Pool & Hot Tub Alliance, the average residential pool holds 15,000-20,000 gallons of water. Accurate volume calculations prevent over- or under-dosing of chemicals, which can lead to unsafe water conditions or wasted money. Understanding evaporation rates also helps budget for water costs.
For irregular shapes, divide pool into sections and calculate each separately.
| Pool Size (ft) | Approx Gallons | Fill Time (8 hrs) |
|---|---|---|
| 12 x 24 x 4 | 8,640 gal | 17 hours |
| 16 x 32 x 5 | 19,200 gal | 38 hours |
| 18 x 36 x 5.5 | 26,730 gal | 53 hours |
| 20 x 40 x 6 | 36,000 gal | 72 hours |
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Rectangular: Length x Width x Avg Depth x 7.5 = gallons. Circular: Diameter^2 x Depth x 5.9 = gallons. Average pool is 15,000-20,000 gallons.
At $5/1,000 gallons, filling a 20,000 gallon pool costs $100. Evaporation loses 1/4 to 1/2 inch per day (100-200 gal) requiring top-offs.
Completely drain and refill every 5-7 years for residential pools. Commercial pools may need more frequent changes. Regular maintenance extends water life.