Above Ground Pool Gallons Chart
These US gallon figures use the pool's geometry and the exact US gallon (231 cubic inches) with the international foot (0.3048 m). They are rounded half-up to the nearest gallon. Use the water depth, not the wall height. Water normally sits a few inches below the top of the wall, so a 52-inch wall may hold roughly 46-48 inches of water. Measure yours before you treat or fill.
Round above ground pools (US gallons)
| Pool | 42 in water | 48 in water | 54 in water |
|---|---|---|---|
| 12 ft round | 2,961 | 3,384 | 3,807 |
| 15 ft round | 4,627 | 5,288 | 5,949 |
| 18 ft round | 6,662 | 7,614 | 8,566 |
| 21 ft round | 9,068 | 10,364 | 11,659 |
| 24 ft round | 11,844 | 13,536 | 15,228 |
| 27 ft round | 14,991 | 17,132 | 19,274 |
| 30 ft round | 18,507 | 21,151 | 23,795 |
| 33 ft round | 22,393 | 25,592 | 28,791 |
Oval above ground pools (US gallons)
Most above ground oval pools have straight sides and semicircular ends. This chart uses that shape. On the pool water volume calculator, choose Oval (straight sides, round ends). Oval (ellipse) uses π × (length / 2) × (width / 2) and holds less water for the same length and width.
| Pool | 42 in water | 48 in water | 54 in water |
|---|---|---|---|
| 12×24 ft oval | 6,731 | 7,693 | 8,654 |
| 15×30 ft oval | 10,518 | 12,020 | 13,523 |
| 16×32 ft oval | 11,967 | 13,676 | 15,386 |
| 18×33 ft oval | 13,732 | 15,693 | 17,655 |
| 21×41 ft oval | 20,065 | 22,931 | 25,797 |
Formulas
Round: area = π × (diameter / 2)². Gallons come from that area times water depth in feet, converted with the exact US gallon.
Oval: area = (length − width) × width + π × (width / 2)², where length is the overall length and width is the diameter of the round ends.
Example: 24 ft round, 48 in deep
π × 12² × 4 cubic feet is 13,536 US gallons. Many charts round this to about 13,500. The figures on this page are half-up to a whole gallon.
For your own measurements, including liters, use the pool water volume calculator. To see how long a fill takes, use the fill time calculator.
Related tools and guides
Frequently asked questions
How many gallons is an 18x52 above ground pool?
An 18 ft round pool with 48 inches of water holds 7,614 US gallons. With 46 inches of water it holds 7,297 US gallons. A 52-inch wall is the wall height, not the water depth.
Why do manufacturer charts differ slightly?
Charts can assume a different water depth, a different rounding rule, or a different wall shape. Measure the water depth and use the calculator for your pool.