In bespeak to number out the suitable doses of chemistry for her pool, you require to determine how countless gallons the water it holds. To execute that, you must use a leader to measure your swimming pool to find out these four different numbers; Length, Width, average depth and also a multiplier the determines gallons.

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So below are the formulas to number out exactly how much water is in your swimming pool:These formulas hold true because that both Inground pools too as above ground pools.

Rectangular, Square or Free type Pools:

Length x broad x average Depth x 7.5 = complete gallons

For example: 16′ x 32′ x 4.5′ x 7.5 = 17,280 Gallons

Circular Pools:

Diameter x Diameter x mean Depth x 5.9 = total gallons

For example: 18′ x 18′ x 4′ x 5.9 = 7,646 Gallons

Oval Pools:

Length x width x median Depth x 5.9 = total gallons

For example: 15′ x 30′ x 4′ x 5.9 = 10,620 Gallons

How to recognize the average Depth the a swimming Pool whereby the bottom slopes:

Below is a side-shot of the “typical” inground swimming pool that has a shallow end (see “D”), then a slope that leads right into the deep end (see “C”).


First measure up the depth the “D”, the shallow end (usually everywhere from 3′ come 5′), and then measure the depth that “C”, the deep finish (usually anywhere in between 6′ and also 12′) . Then, include them together and also divide through 2. This is the mean depth of her pool.

For example, if your shallow end “D” is 3′, and also your deep finish “C” is 8′, this would be her formula because that the typical Depth:

3′ + 8′ = 11′

11′ split by 2 = 5.5.

Therefore, in this example, your median depth would be 5 1/2 feet.

Most common Sizes that Inground rectangle-shaped Pools

Below, we have created some comfortable charts that the most well-known sizes the poolsand how plenty of gallons of water are in them.

See more: 10 Oz Is How Many Grams Converter, 1/10 Oz In Grams


12′ X 24′8,6409,72010,80011,88012,960
14′ X 28′11,76013,23014,70016,17017,640
15′ X 30′13,50015,20019,90018,60020,250
16′ X 32′15,40017,30019,20021,10023,040
18′ X 36′19,40021,90024,30026,70029,160
20′ X 40′24,00027,00030,00033,00036,000
25′ X 45′33,75037,96842,18746,40650,625
25′ X 50′37,50042,20046,90051,60056,250
30′ X 50′45,00050,52556,25061,87567,500

Most typical Sizes Of above Ground Pools


Above ground Pools with a Depth that 48″ (4′)



12′ Round3,398
15′ Round5,310
18′ Round7,646
21′ Round10,407
24′ Round13,593
27′ Round17,204
28′ Round18,502
30′ Round21,240
33′ Round25,700
15′ x 30′ Oval10,620



12′ Round3,823
15′ Round5,973
18′ Round8,602
21′ Round11,708
24′ Round15,292
27′ Round19,354
28′ Round20,815
30′ Round23,895
33′ Round28,912
15′ x 30′ Oval11,947

More detailed Information for You:

If you are not utilizing a cabinet phone, and are using a desktop computer computer, laptop or tablet, we do have actually a really detailed page with an ext information to add an online Pool Water Calculator on our classic Pool and also Spa desktop site.Click here to watch our E-Z swimming pool Water Calculator page.

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