Like a novice cook who needs to know how much of each ingredient to add to a dish, pool owners need to know how much of their maintenance products they need to add to their water. In order to do this properly, pool owners must know their pool volume — how much water is actually in their pool.
Calculating your pool volume is essential to correctly balancing the water. Making only rough estimates can result in errors and end up causing issues. Over-estimating is a waste of money; under-estimating will result in unsanitary water. If the volume of your pool isn’t in the original documentation, it’s easy to calculate it yourself.
Running The Numbers
Three average measurements are used to calculate pool volume: length, width, and depth. There are more complicated formulas for measuring oddly-shaped pools, but we’ll focus on the traditional pools.
First, carefully record the measurements mentioned above. Second, take each number and multiply them together. Finally, multiply that result by 7.5 (which is approximately how many gallons are in a cubic foot).
The combined formula should look like this:
Length × Width × Depth × 7.5 = Pool Volume (in Gallons)
Once you have this number, you should be able to apply the correct amount of pool chemicals to your pool water and avoid any future dosage issues.
Quick Reference
For your convenience, you can also consult the following charts. They detail the volume of many popular pool sizes.
Above Ground Pool Volume (48″ Wall Height)
| Pool Size | Gallons |
|---|---|
| 15′ Round | 5,300 |
| 18′ Round | 7,600 |
| 20′ Round | 9,400 |
| 24′ Round | 13,600 |
| 27′ Round | 17,200 |
| 28′ Round | 18,500 |
| 11×25 Oval | 6,500 |
| 11×30 Oval | 7,800 |
| 15×25 Oval | 8,900 |
| 15×30 Oval | 10,600 |
| 18×33 Oval | 14,000 |
| 18×38 Oval | 16,100 |
Above Ground Pool Volume (52″ Wall Height)
| Pool Size | Gallons |
|---|---|
| 15′ Round | 5,800 |
| 18′ Round | 8,300 |
| 20′ Round | 10,200 |
| 24′ Round | 15,300 |
| 27′ Round | 18,600 |
| 28′ Round | 20,000 |
| 11×25 Oval | 7,000 |
| 11×30 Oval | 8,400 |
| 15×25 Oval | 9,600 |
| 15×30 Oval | 11,500 |
| 18×33 Oval | 15,200 |
| 18×38 Oval | 17,500 |
In-Ground Pool Volume (Standard Depth)
| Pool Size | Gallons |
|---|---|
| 12×24 Rectangle | 10,800 |
| 16×32 Rectangle | 19,200 |
| 16×36 Rectangle | 21,600 |
| 18×36 Rectangle | 24,300 |
| 20×40 Rectangle | 30,000 |
| 16×32 Oval | 17,200 |
| 18×36 Oval | 21,700 |
| 18×36 Oval | 21,700 |
| 20×40 Oval | 26,800 |
| 17×33 Grecian | 19,700 |
| 17×37 Grecian | 22,200 |
| 20×36 Grecian | 24,300 |
| 20×44 Grecian | 30,300 |
| 16×30 Kidney | 14,900 |
| 16×34 Kidney | 16,500 |
| 20×38 Kidney | 20,200 |
For more information on pool size or chemical usage, check our complete blog library, reach out to one of our knowledgeable staff members at your local Leslie’s store, or call 1-800-LESLIES. At Leslie’s, your pool is our passion.