How to read these charts
- Measure inside wall to inside wall, at the waterline.
- Measure water depth from the surface down to the floor, not the top of the wall.
- For a sloped floor, add the shallow and deep depths and divide by two.
- Find your size in the table and read the gallons column that matches your depth.
If your depth sits between two columns, take the closer column and adjust proportionally. Volume changes in a straight line with depth, so a pool filled 10 percent deeper holds 10 percent more water.
Round pool volume by size
Round above ground pools come in 48 inch and 52 inch walls. Filled properly they sit at roughly 4.0 ft and 4.33 ft of water.
Round pool volume at 4.0 ft and 4.33 ft water depth
| Diameter | 4.0 ft (US gal) | 4.0 ft (litres) | 4.33 ft (US gal) | 4.33 ft (litres) |
|---|---|---|---|---|
| 10 ft | 2,350 | 8,896 | 2,544 | 9,630 |
| 12 ft | 3,384 | 12,810 | 3,663 | 13,867 |
| 14 ft | 4,606 | 17,436 | 4,986 | 18,875 |
| 15 ft | 5,288 | 20,016 | 5,724 | 21,667 |
| 16 ft | 6,016 | 22,774 | 6,513 | 24,653 |
| 18 ft | 7,614 | 28,823 | 8,242 | 31,201 |
| 20 ft | 9,400 | 35,584 | 10,176 | 38,520 |
| 21 ft | 10,364 | 39,231 | 11,219 | 42,468 |
| 24 ft | 13,536 | 51,241 | 14,653 | 55,468 |
| 27 ft | 17,132 | 64,852 | 18,545 | 70,202 |
| 28 ft | 18,425 | 69,745 | 19,945 | 75,499 |
| 30 ft | 21,151 | 80,064 | 22,896 | 86,669 |
| 33 ft | 25,592 | 96,878 | 27,704 | 104,870 |
Different depth? The round pool volume calculator takes any diameter and depth in feet, inches, metres or centimetres.
Oval pool volume by size
Oval pool volume at 4.0 ft and 4.33 ft water depth
| Size (L x W) | 4.0 ft (US gal) | 4.33 ft (US gal) |
|---|---|---|
| 15 x 10 ft | 3,525 | 3,816 |
| 18 x 12 ft | 5,076 | 5,495 |
| 20 x 12 ft | 5,640 | 6,106 |
| 21 x 13 ft | 6,416 | 6,945 |
| 24 x 12 ft | 6,768 | 7,327 |
| 24 x 16 ft | 9,024 | 9,769 |
| 30 x 15 ft | 10,575 | 11,448 |
| 33 x 18 ft | 13,959 | 15,111 |
Rectangular inground pool volume by size
Inground pools are usually quoted at average depth. A 3 ft shallow end with an 8 ft deep end averages 5.5 ft. A shallow family pool with a flat 4 ft floor and a 5 ft end averages about 4.5 ft.
Rectangular pool volume in US gallons by average depth
| Size | 4.5 ft avg | 5.0 ft avg | 5.5 ft avg | 5.0 ft in litres |
|---|---|---|---|---|
| 10 x 20 ft | 6,732 | 7,481 | 8,229 | 28,317 |
| 12 x 20 ft | 8,079 | 8,977 | 9,874 | 33,980 |
| 12 x 24 ft | 9,695 | 10,772 | 11,849 | 40,776 |
| 14 x 24 ft | 11,311 | 12,567 | 13,824 | 47,572 |
| 14 x 28 ft | 13,196 | 14,662 | 16,128 | 55,501 |
| 15 x 25 ft | 12,623 | 14,026 | 15,429 | 53,094 |
| 15 x 30 ft | 15,148 | 16,831 | 18,514 | 63,713 |
| 16 x 32 ft | 17,235 | 19,150 | 21,065 | 72,491 |
| 16 x 36 ft | 19,390 | 21,544 | 23,698 | 81,552 |
| 18 x 36 ft | 21,813 | 24,237 | 26,661 | 91,747 |
| 20 x 40 ft | 26,930 | 29,922 | 32,914 | 113,267 |
| 25 x 50 ft | 42,078 | 46,753 | 51,429 | 176,980 |
Small pools, spas and plunge pools
| Type | Typical size | US gallons |
|---|---|---|
| Hot tub, 4 seat | 6.5 ft round x 2.8 ft | 700 to 800 |
| Hot tub, 6 seat | 7.5 ft square x 3 ft | 400 to 500 (seat volume removed) |
| Plunge pool | 8 x 14 ft x 4 ft | 3,350 |
| Cocktail pool | 10 x 20 ft x 3.5 ft | 5,236 |
| Swim spa | 7 x 15 ft x 4 ft | 3,140 |
Spa numbers vary a lot because seats and footwells take up space. Use the hot tub volume calculator for a closer figure, or the plunge pool volume calculator for compact pools.
Why your real volume may differ
- Box sizes are outer dimensions. Frames and liners eat several inches of water width.
- Above ground pools are rarely filled to the top ring, so real depth runs 6 to 8 inches below the wall.
- Tanning ledges, steps and benches remove water, usually 100 to 400 gallons.
- Attached spas and spillways add water that charts never include.
- Vinyl liner pools with a hopper bottom hold less than the flat floor assumption.
For anything non standard, run the exact figures through the pool volume calculator, then keep the number written inside your equipment pad door. Every dose you ever mix depends on it.
Related video
pool volume by size FAQs
How many gallons is a 16 by 32 ft pool?
About 19,150 US gallons at a 5 ft average depth. At 4.5 ft it holds 17,235 gallons and at 5.5 ft it holds 21,065 gallons.
How many gallons is a 24 ft round pool?
A 24 ft round pool holds 13,536 gallons at 4 ft of water and 14,653 gallons at 4.33 ft, the usual depth in a 52 inch wall.
Does wall height equal water depth?
No. Above ground pools are filled 6 to 8 inches below the top of the wall, so a 52 inch wall usually carries about 4.33 ft of water.
How many gallons is a 12 by 24 ft pool?
About 10,772 US gallons at a 5 ft average depth, which is 40,776 litres.
More pool guides
- Pool Volume Formula for Every Pool Shape
All the pool volume formulas, the constants behind them, and a worked example for each shape.
- Average Pool Volume by Pool Type
What a typical pool holds, by type, plus what the average costs to run.
- Olympic Pool Volume and How It Is Calculated
The exact size and volume of an Olympic pool, plus how many home pools fit inside one.