Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Pool volume (gallons)
19,149
Volume (cubic feet)
2,560
Psst — share this and help Rex grow
One click, a permanent link with your numbers baked in.
How to use this
- 1Enter pool shape.
- 2Enter length (or diameter if round) (ft).
- 3Enter width (ignored if round) (ft).
- 4Enter average depth (ft).
- 5Read your pool volume (gallons) on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Pool volume in gallons is calculated from the pool's shape, dimensions, and average depth, converted using the standard 7.48 gallons per cubic foot of water. This calculator supports rectangular and round pools with an average-depth input to handle sloped pool floors.
Worked example
Using the values the calculator loads with:
Inputs
- Pool shape: Rectangular
- Length (or diameter if round): 32 ft
- Width (ignored if round): 16 ft
- Average depth: 5 ft
Results
- Pool volume (gallons): 19,149
- Volume (cubic feet): 2,560
What each field means
Inputs
- Pool shape
- Pick the option that matches your situation — the maths changes per option. Choices: Rectangular, Round.
- Length (or diameter if round) (ft)
- The length (or diameter if round) used in the calculation, measured in ft. Starts at 32 ft so you have a working example on load.
- Width (ignored if round) (ft)
- The width (ignored if round) used in the calculation, measured in ft. Starts at 16 ft so you have a working example on load.
- Average depth (ft)
- The average depth used in the calculation, measured in ft. Starts at 5 ft so you have a working example on load. Accepted range: 1–15 ft.
Results
- Pool volume (gallons)
- Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Volume (cubic feet)
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How many gallons is my pool?
A rectangular 32x16-foot pool averaging 5 feet deep holds 32 × 16 × 5 × 7.48 = 19,148.8 gallons, or about 19,149 gallons.
How do I find average depth for a sloped pool?
Add the shallow-end depth and deep-end depth together and divide by two — for a pool going from 3 feet to 8 feet, average depth is 5.5 feet.
Why multiply by 7.48?
That's the standard conversion factor for gallons per cubic foot of water (there are exactly 7.48052 gallons in one cubic foot), which converts your volume calculation from cubic feet into the gallons pool chemical dosing charts use.
Why do I need to know my pool's gallon count?
Chlorine, shock, and other pool chemical dosing instructions are almost always given per 10,000 gallons, so accurate volume is essential to avoid under- or over-treating your water.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). How Many Gallons Is My Pool?. Retrieved from https://www.revenuelab.fyi/toolbox/how-many-gallons-is-my-pool
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/how-many-gallons-is-my-pool" target="_blank" rel="noopener">How Many Gallons Is My Pool? — RevenueLab</a> (2026).</p>
Source: [How Many Gallons Is My Pool? — RevenueLab](https://www.revenuelab.fyi/toolbox/how-many-gallons-is-my-pool) (2026).