In order to figure out the proper doses of chemicals for your pool, you need to determine how plenty of gallons that water it holds. To do that, you must use a leader to measure your pool to uncover out these four different numbers; Length, Width, mean depth and also a multiplier that 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 organize true for both Inground pools too as over ground pools.

Rectangular, Square or Free kind Pools:

Length x broad x typical 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 average Depth x 5.9 = full gallons

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

Oval Pools:

Length x broad x mean Depth x 5.9 = full gallons

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

How to determine the median Depth of a swimming Pool whereby the bottom slopes:

Below is a side-shot the the “typical” inground pool that has a shallow finish (see “D”), climate a slope that leads into the deep finish (see “C”).


First measure up the depth the “D”, the shallow end (usually all over from 3′ to 5′), and also then measure up the depth the “C”, the deep finish (usually anywhere between 6′ and 12′) . Then, add them together and also divide by 2. This is the average depth of her pool.

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

3′ + 8′ = 11′

11′ separated by 2 = 5.5.

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

Most typical Sizes of Inground rectangle-shaped Pools

Below, us have produced some comfortable charts of the most well-known sizes that poolsand how countless gallons the water room in them.

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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 of 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 in-depth Information for You:

If you space not using a cabinet phone, and also are utilizing a desktop computer computer, laptop or tablet, us do have a really detailed web page with more information plus an online Pool Water Calculator on our classic Pool and also Spa desktop site.Click below to check out our E-Z swimming pool Water Calculator page.

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