Pool Volume Calculator
Pick your pool shape and enter the dimensions to get the volume in cubic feet and gallons.
What your result means
Gallons is the number you'll plug into every chemical-dosing calculator, figured at 7.48 gallons a cubic foot. Average depth is the shallow plus deep end divided by two. Real pools have curved walls and sloped floors, so treat this as a close approximation, not an exact fill.
How to use this calculator
- Pick your pool shape.
- Enter length and width (in ft).
- Calculate average depth (shallow + deep) / 2.
- Read cubic feet and gallons.
- Use gallons for chemical dosing.
The formula
For a rectangle the volume is length times width times average depth. Round and oval pools use the circle and ellipse area times depth. Multiply cubic feet by 7.48 for gallons.
Worked example
Say you've got a 30 by 15 ft rectangular pool with a 5 ft average depth. That's 2,250 cubic feet, which is 16,831 gallons.
Pool volume quick reference
| Item | Value |
|---|---|
| 1 cubic foot | 7.48 gallons |
| Average depth | (shallow + deep) / 2 |
| Typical residential pool | 15,000 – 25,000 gal |
Tips & gotchas
- Average depth is the shallow end plus the deep end, divided by two.
- One cubic foot is 7.48 gallons.
- Use the gallons figure for every chemical-dosing calculator.
- For round and oval pools, length is the diameter.
- Pools have curved walls, so this is a close approximation.
Frequently asked questions
How many gallons in a pool?
Use the calculator. An average residential pool holds 15,000 to 25,000 gallons.
How do I find average depth?
Add the shallow and deep end depths and divide by two.
How many gallons in a cubic foot?
About 7.48.
What about pools with sloped bottoms?
Use the average depth; this handles a uniform depth.
Why do I need pool volume?
For chemical dosing, heater sizing, and estimating water cost.
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