Pool Volume Calculator
Work out how many gallons or liters of water a rectangular, round or oval pool holds from its size and depths.
Pool volume
18,193 gallons
- Liters
- 68,867 L
- Cubic feet
- 2,432 ft³
The pool holds about 18,193 US gallons, which is about 68,867 liters.
Calculation breakdown
| Step | Formula | Result |
|---|---|---|
| Surface area | 32 × 16 | 512.00 sq ft |
| Average depth | (3.5 + 6) ÷ 2 | 4.750 ft |
| Volume | 512 × 4.75 | 2,432.00 ft³ |
| Gallons | 2,432 ft³ × 7.48052 | 18,193 gal |
How it works
Choose the shape, enter its size and the depths at the shallow and deep ends. Use the same depth in both for a pool with a flat floor.
Worked example
A rectangular pool 32 ft by 16 ft, 3.5 ft deep at one end and 6 ft at the other:
- Area: 32 × 16 = 512 sq ft
- Average depth: (3.5 + 6) ÷ 2 = 4.75 ft
- Volume: 512 × 4.75 = 2,432 cubic feet
- Gallons: 2,432 × 7.48052 = 18,193 gallons, which is about 68,867 liters
Rounding
Gallons and liters are shown to the nearest whole number.
Sources
Frequently asked questions
How do you calculate the volume of a pool?
Multiply the surface area by the average depth. A rectangular pool 32 feet by 16 feet with an average depth of 4.75 feet has 512 × 4.75 = 2,432 cubic feet. Multiply by 7.48052 to convert to gallons, which gives about 18,193 gallons.
How many gallons are in a cubic foot?
A US gallon is 231 cubic inches, which is 3.785 liters, so one cubic foot holds about 7.48052 gallons. NIST Handbook 44 defines the gallon this way.
How do I find the average depth?
If the floor slopes evenly from the shallow end to the deep end, add the two depths and divide by 2. A pool 3.5 feet deep at one end and 6 feet at the other averages 4.75 feet. If the floor has a steep drop or a hopper, the average depth is different, so treat the result as an estimate.
How do I measure an oval pool?
Measure the longest length and the widest width. The area of an oval, or ellipse, is π ÷ 4 times length times width, which is about 78.5% of the area of the rectangle that surrounds it. The calculator does this for you.
What is the volume used for?
Pool chemicals, salt, heaters and pumps are all sized by the number of gallons in the pool. Use the volume with the pool salt calculator on this site. Fill the pool to its normal operating level, not to the top of the wall, when you measure depth.
Estimates only. Pools with steep slopes, steps, hoppers or curved edges can hold more or less than the simple shape suggests.