Pool Volume Calculator
This pool volume calculator tells you how many gallons your pool holds. Choose a rectangle, round, oval or kidney shape, enter the size and either one depth or the shallow and deep ends, and you get gallons, liters and cubic feet, plus the time a hose takes to fill it. If you enter the dose from a product label, it also scales that dose to your pool.
Updated
Results
- Pool volume (liters)
- Volume (cu ft)
- Surface area (sq ft)
- Average depth (ft)
- Time to fill with a hoseAt the flow you entered
- Chlorine amount needed (same unit as the label)Shown when you enter a label dose
- Salt amount needed (same unit as the label)Shown when you enter a label dose
Results are estimates. See the methodology below.
How to use the pool volume calculator
- Pick the shape. For a kidney pool, enter the length and the widths of the two lobes, A and B, at their widest points.
- Choose Constant depth for above-ground pools, or Sloped and enter the shallow and deep ends. Measure to the water line, not the top of the wall.
- Enter your hose flow in gallons per minute. To find it, time how long a 5-gallon bucket takes to fill: 30 seconds means 10 gpm.
- In Advanced options, type the chlorine or salt dose per 10,000 gal exactly as printed on your product label, in any unit.
How the calculator works
- Rectangle: length × width
- Round: π × (diameter ÷ 2)²
- Oval: π ÷ 4 × length × width (a true ellipse)
- Kidney: 0.45 × (A + B) × length
- Average depth = (shallow + deep) ÷ 2
- Cubic feet = surface × average depth
- Gallons = cubic feet × 7.4805; liters = cubic feet × 28.317
- Fill time = gallons ÷ hose flow
- Dose = label dose × gallons ÷ 10,000
A US gallon is defined as 231 cubic inches, so a cubic foot (1,728 in³) holds about 7.48 gallons. Pool retailers such as Leslie's round this to 7.5, which gives results about 0.26 % higher: 22,080 instead of 22,023 gallons for the first example below. The kidney factor of 0.45 is an industry approximation, not exact geometry; freeform pools are not covered.
Worked examples
In-ground rectangle, 32 × 16 ft, 3.5 to 8 ft deep
The surface is 512 sq ft and the average depth 5.75 ft, so the pool holds 2,944 cu ft, about 22,023 gallons (83,365 liters). At 10 gpm, filling it takes about 36 h 42 min. With a 3 ft shallow end instead, the average drops to 5.5 ft and the volume to 21,065 gallons.
Round above-ground pool, 18 ft across, 4 ft of water
The surface is 254.5 sq ft and the volume 7,614 gallons (28,823 liters). A 10 gpm hose fills it in about 12 h 41 min; at 8 gpm it takes about 15 h 51 min.
Oval and kidney pools
| Pool | Surface (sq ft) | Gallons |
|---|---|---|
| Oval 30 × 15 ft, 4.5 ft deep | 353.4 | 11,897 |
| Kidney 30 ft long, A 10 ft, B 14 ft, 3 to 6 ft deep | 324.0 | 10,907 |
Scaling a label dose
If a label gives a dose per 10,000 gallons, the 22,023-gallon pool needs about 2.2 times that amount. Enter the label figure and the calculator does the multiplication in the same unit.
Reading the result
The volume is an estimate. Steps, benches, hopper-shaped deep ends and a water line below the top of the wall all change the real number. The calculator does not give chemistry advice: it has no target levels for chlorine, salt, pH or alkalinity. Follow the product label and your salt-cell manufacturer's instructions, and read the label before storing or handling pool chemicals. For a concrete pool deck around it, our concrete calculator helps, and our gravel calculator covers a stone border.
Frequently asked questions
How many gallons are in my pool?
Multiply the surface area by the average depth to get cubic feet, then by 7.48. A 32 × 16 ft pool averaging 5.75 ft deep holds about 22,023 gallons.
How many gallons is a cubic foot of water?
About 7.48 US gallons, because a gallon is 231 cubic inches and a cubic foot is 1,728. Many pool charts round it to 7.5.
How do I find the average depth?
Add the shallow-end and deep-end depths and divide by two. A pool that goes from 3.5 to 8 ft averages 5.75 ft.
How long does it take to fill a pool with a hose?
Divide the gallons by your hose flow. An 18 ft round pool with 4 ft of water (7,614 gallons) takes about 12 h 41 min at 10 gpm. Water pressure varies, so time a bucket to find your real flow.
How much chlorine does my pool need?
That depends on the product and on your water, so the calculator doesn't recommend a dose. Enter the dose from your product label and it scales it to your volume.
Can I mix different pool chemicals?
The CDC advises keeping incompatible chemicals such as acid and chlorine apart, not mixing different chlorine products, and following label directions.
Sources
This is a volume estimate based on the shape and depths you enter. For chemical doses, always follow the product label and the equipment manufacturer's instructions.