Pool Volume Calculator
Estimate swimming-pool volume, fill time, circulation flow, water weight and filling cost from pool dimensions and average depth.
Default project preview
17,673 gallons
Fill time
29.5 hours
Circulation target
36.8 gal/min
Cubic volume
66.9 m³
Water weight
66.9 tonnes
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Pool length
Enter this project assumption in ft. The current imperial default is 30 ft.
Pool width
Enter this project assumption in ft. The current imperial default is 15 ft.
Shallow depth
Enter this project assumption in ft. The current imperial default is 3.5 ft.
Deep depth
Enter this project assumption in ft. The current imperial default is 7 ft.
Shape factor
Enter this project assumption in %. The current imperial default is 100 %. Minimum: 10. Maximum: 100.
Fill flow
Enter this project assumption in gal/min. The current imperial default is 10 gal/min.
Target turnover time
Enter this project assumption in hours. The current imperial default is 8 hours.
Water price
Enter this project assumption in per 1,000 gal. The current imperial default is 8 per 1,000 gal. Minimum: 0.
How to read the outputs
Fill time
10 gal/min. Default preview: 29.5 hours.
Circulation target
8-hour turnover. Default preview: 36.8 gal/min.
Cubic volume
water volume. Default preview: 66.9 m³.
Water weight
approximate metric mass. Default preview: 66.9 tonnes.
Surface area
plan area. Default preview: 450 ft².
Fill cost
using entered water price. Default preview: $141.38.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Average depth = (shallow depth + deep depth) ÷ 2. Volume = length × width × average depth × shape factor. Circulation flow = volume ÷ turnover minutes.
Reviewed project guidance
How to use this estimate in a real project
Last reviewed: July 29, 2026
Use this calculator to estimate pool water volume from plan shape and average depth. The result supports chemical dosing, heating and pump-runtime planning but does not size circulation or safety systems.
Calculation steps
- 1Choose the plan shape that best fits the pool.
- 2Measure waterline length and width.
- 3Calculate average depth from shallow and deep sections or sectional volumes.
- 4Convert geometric volume to gallons or litres.
Worked numerical example
A rectangular 30 ft × 15 ft pool averaging 5 ft deep contains about 16,830 gallons.
Purchasing and rounding
Use volume with product label rates for chemicals or heating calculations. Never dose from a rough estimate when precise water testing is required.
Interpret the result
Average depth is the most sensitive input after plan area. Sloped floors and benches can make a simple average less accurate.
Page-specific assumptions
- Selected shape approximates the pool.
- Dimensions are measured at the waterline.
- Average depth is representative.
- Steps and benches are small or separately deducted.
Common mistakes
- Using maximum depth.
- Measuring exterior shell dimensions.
- Ignoring irregular sections.
- Using volume alone to select pumps or drains.
Primary and technical references
BuildMeter provides planning estimates, not engineering, architectural, electrical, mechanical, plumbing, permit or code approval. Review the methodology and verify final decisions with product documentation and qualified professionals.
FAQ
Pool Volume Calculator questions
How is average pool depth calculated?+
For a steadily sloped floor, the shallow and deep depths are averaged. Complex floors need a more detailed calculation.
What turnover time should be used?+
Requirements vary by pool type, jurisdiction and equipment. Follow local standards and equipment guidance.
Why might measured fill volume differ?+
Steps, benches, curves and the actual waterline all change the final volume.