Pool Volume Calculator
Calculate how many gallons your pool holds.
Common Pool Sizes and Volumes
Approximate gallons for typical residential pools
| Pool Size | Avg Depth | Gallons | Liters | Weight (lbs) |
|---|---|---|---|---|
| 12x24 ft rect | 5 ft | 10,778 | 40,800 | 89,893 |
| 16x32 ft rect | 5.5 ft | 21,067 | 79,750 | 175,697 |
| 18x36 ft rect | 5.5 ft | 26,658 | 100,918 | 222,325 |
| 15 ft round | 4 ft | 5,288 | 20,019 | 44,100 |
| 18 ft round | 4 ft | 7,614 | 28,824 | 63,501 |
| 24 ft round | 4 ft | 13,536 | 51,243 | 112,890 |
How We Calculate This
This pool volume calculator uses established formulas and industry-standard data to provide accurate estimates.
- Enter your specific values into the calculator fields above
- Our algorithm applies the relevant formulas using your inputs
- Results are calculated instantly in your browser — nothing is sent to a server
- Review the detailed breakdown to understand how each factor affects your result
These calculations are estimates based on standard formulas. For critical decisions, always consult a qualified professional.
How to Convert Oven Recipes to Air Fryer
This calculator determines pool water volume using standard geometry formulas for each pool shape, combined with average depth calculations.
The basic rule:
- Rectangular: Volume = length x width x average depth x 7.48 gallons/cu ft
- Round: Volume = pi x radius^2 x average depth x 7.48
- Oval: Volume = pi x (length/2) x (width/2) x average depth x 7.48
- Average depth = (shallow end + deep end) / 2
- 1 cubic foot = 7.48052 gallons
- 1 gallon of water weighs 8.34 pounds
For pools with irregular shapes, divide the pool into simpler sections, calculate each separately, and add the volumes together. For kidney-shaped pools, use 0.45 x length x width x average depth x 7.48 as an approximation.
When Would You Use This Calculator?
This pool volume calculator is designed for anyone who needs quick, reliable estimates without complex spreadsheets or professional consultations.
- When you need a quick estimate before committing to a purchase or project
- When comparing different options or scenarios side by side
- When planning a budget and need to understand potential costs
- When you want to verify a quote or estimate you've received from a professional
- When teaching or learning about the concepts behind these calculations
Frequently Asked Questions
How many gallons is a standard swimming pool?
A typical residential rectangular pool (30x15 ft, 3-8 ft depth) holds about 12,000-24,000 gallons. A standard 12x24 ft pool with 5.5 ft average depth is about 11,880 gallons. An 18-foot round above-ground pool (4 ft deep) holds about 7,600 gallons.
How do I measure pool depth?
Measure the shallow end depth and deep end depth separately with a measuring tape from the waterline to the floor. For pools with a constant depth, use that single measurement for both. The calculator averages the two depths for volume calculation.
Why do I need to know my pool volume?
Pool volume is essential for: chemical dosing (chlorine, pH adjusters, algaecide), heater sizing, pump and filter selection, water replacement cost estimates, and winterizing calculations. Incorrect volume estimates lead to under- or over-dosing chemicals.
How much does it cost to fill a pool?
At average US water rates ($4 per 1,000 gallons), a 15,000-gallon pool costs about $60 to fill. Rates vary from $2 to $12 per 1,000 gallons. Water delivery by truck costs $200-$600 per load (6,000-8,000 gallons). Many areas offer a sewer credit for pool fills.
How do I calculate an irregular shaped pool?
For kidney or freeform pools: measure the longest length and widest width, multiply by 0.45 (kidney) or 0.40-0.50 (freeform) instead of using the full rectangle. Or divide the pool into simpler geometric sections and calculate each separately.
How much does the water in my pool weigh?
Water weighs 8.34 lbs per gallon. A 15,000-gallon pool holds about 125,000 lbs (62.5 tons) of water. This is important for structural considerations, especially for above-ground pools and rooftop installations.