rectangle pool, 24 ft x 12 ft x 4.5 ft average depth
- Cubic feet
- 1296
- Shape factor
- 1
- Gallons per cubic foot
- 7.48052
Sloped bottoms, steps, benches, freeform curves, and actual water line can change real pool volume.
Pool Volume Calculator
Use this free pool volume calculator to estimate U.S. gallons for rectangular, round, or oval pools from shape, measurements, and average water depth.
Inputs explained Result checks Example values Runs in your browser
Formula steps
- Find surface area from the selected shape.
- Multiply by average depth for cubic feet.
- Multiply cubic feet by 7.48052 to estimate U.S. gallons.
How to use the Pool Volume Calculator
- Choose rectangle, round, or oval pool shape.
- Enter length, width or diameter, and average depth in feet.
- Press Calculate pool volume to estimate cubic feet and U.S. gallons.
- Use average depth and remember steps, benches, curves, and waterline height affect real volume.
What people use it for
Estimate gallons before adding pool chemicals.
Compare rectangular, round, and oval pool volume.
Use average depth for shallow and deep ends.
Plan fill volume or rough equipment context.
Check whether a pool heater, pump, or filter estimate uses a realistic gallon number.
Quick examples
Rectangle pool
24 ft x 12 ft x 4.5 ft average depth9,695 gallons
Round pool
18 ft diameter, 4 ft depth7,614 gallons
Oval pool
30 ft x 15 ft x 4.3 ft average depth11,368 gallons
Lap-style rectangle
12 ft x 24 ft x 5 ft average depth10,772 gallons
Need the guide or a nearby tool?
Need a slower walkthrough, a related calculator, or the full library? These links keep you close to the task you started.
- How to use the Pool Volume Calculator See slower examples, input meanings, formula notes, result limits, and mistakes to avoid.
- Home & Projects Browse related calculators and utilities in the same category.
- Calculator and utility guides Find more guides that use real tool inputs and example numbers.
- All free tools Search every live tool, converter, calculator, AI helper, and browser utility.
Frequently asked questions
Plain-language answers about when to use the tool, what it does with your inputs, what to double-check, and how privacy works.
When should I use the Pool Volume Calculator?
Use it when your task matches one of these common needs: Estimate gallons before adding pool chemicals. Compare rectangular, round, and oval pool volume. It works best when you already know pool shape, length or diameter, width or diameter, and average water depth.
What is the Pool Volume Calculator doing with my inputs?
In plain language: Rectangle cubic feet = length x width x average depth. Round or oval cubic feet = length x width x average depth x pi / 4. U.S. gallons = cubic feet x 7.48052. The examples on the page are there so you can compare your inputs with a real pool-gallon estimate before copying the answer.
What do the main Pool Volume Calculator inputs mean?
Pool shape: the simple shape used for the volume formula: rectangle, round, or oval. Length or diameter: the long measurement for rectangles and ovals, or the diameter for round pools. Width or diameter: the short measurement for rectangles and ovals, or the same diameter again for a round pool. Average depth: the average water depth, useful when the shallow and deep ends differ. Measure from the waterline, not the top of the wall.
How should I read the Pool Volume Calculator answer?
Read the headline estimate first, then check the material, waste, coverage, and unit lines. For project tools, the supporting lines are often the difference between a rough idea and a list you can actually shop from.
What should I double-check before trusting the answer?
This is a shape-based estimate. Sloped bottoms, steps, benches, freeform shapes, kidney shapes, rounded corners, spas, waterline height, deep hoppers, and measurement error can change real pool volume and chemical dosing. Double-check chemical dosing against product labels, water tests, and your pool professional when the pool shape is unusual or the dose matters.
How do I calculate pool gallons?
Find cubic feet from the pool shape and average depth, then multiply by 7.48052. For a rectangle, that is length x width x average depth x 7.48052.
How do I find average pool depth?
For a steady slope, add shallow depth and deep depth, then divide by 2. For example, 3 feet plus 6 feet is 9, divided by 2, so average depth is 4.5 feet.
Should I use wall height or water depth?
Use actual water depth from the waterline to the floor. Wall height can overstate gallons if the water sits below the top rail or coping.
How do I enter a round pool?
Choose round, then enter the diameter in both length and width fields. The calculator applies the pi / 4 shape factor for the circular surface.
Why do pool calculators use 7.48 or 7.5?
One cubic foot is about 7.48052 U.S. gallons. Many pool charts round that to 7.5 for quick mental math, but this calculator uses 7.48052.
Can I use this for an oval pool?
Yes, choose oval and enter the long and short measurements. The calculator uses the same pi / 4 surface factor as an ellipse-style oval estimate.
Can I use this for a kidney or freeform pool?
Only as a rough starting point. For irregular pools, break the pool into simpler sections or compare the estimate with fill-meter, builder, or chemical-adjustment clues.
Can I dose pool chemicals from this number?
Use it as the starting gallon estimate, then follow chemical labels and water-test results. A wrong gallon number can make chemical doses too weak or too strong.
Does the site save what I enter?
No. The calculator runs in your browser tab. Your recent answers stay only on the page while you use it, and they are not sent to a server.