Pool Volume Calculator in Litres and Gallons

A pool volume calculator quickly estimates how many gallons or liters of water your pool holds based on its shape, length, width, average depth, and diameter for round pools. Knowing the exact pool capacity helps balance chemicals accurately, size filtration systems correctly, and manage water costs more efficiently. This tool works for inground and above-ground pools, giving precise results for maintenance and treatment planning.

What is a Pool Volume Calculator?

A pool volume calculator estimates how much water a swimming pool holds based on its shape and dimensions. It simplifies chemical dosing and helps optimize filtration settings. Online versions use built-in formulas to give results instantly.

Why Do You Need to Calculate Pool Volume?

You need pool volume to dose chemicals correctly and maintain safe water balance. Proper measurement prevents chlorine overuse, which irritates skin and eyes, and underuse, which allows bacteria growth. Pool size also determines filtration runtime and heating requirements.

How Do You Calculate Pool Volume Manually?

Pool volume is calculated using standard formulas. For rectangular pools, multiply length × width × average depth × 7.5 to get gallons. For round pools, use diameter × diameter × average depth × 5.9. Oval pools use length × width × average depth × 6.7.

How Do You Measure Average Depth?

You find average depth by adding the shallow end and deep end depths and dividing by two. For example, if the shallow end is 3 feet and the deep end is 8 feet, the average depth equals 5.5 feet. This ensures more accurate calculations.

What Types of Pools Can You Calculate Volume For?

Pool volume can be calculated for rectangular, round, and oval pools using formulas. Freeform pools with irregular shapes require breaking the pool into smaller measurable sections. Most online calculators provide options for common pool designs and shapes.

How Does an Online Pool Volume Calculator Work?

An online calculator requires pool dimensions such as length, width, and depth. It applies the correct formula based on pool shape and converts the result into gallons or liters. This method eliminates errors and saves time compared to manual calculations.

What Factors Affect Pool Volume Accuracy?

Accuracy decreases if the pool has sloped bottoms, steps, or attached spas. Measuring only the maximum depth instead of average depth leads to incorrect results. Irregular freeform designs also introduce calculation variations.

How to Use Pool Volume for Pool Maintenance?

Pool volume determines how much chlorine, algaecide, or pH balancer you need. It also helps calculate the correct runtime for filters and pumps. Pool heaters use volume data to estimate energy requirements and heating times.

Common Mistakes When Calculating Pool Volume

Many pool owners use the maximum depth instead of the average depth, which inflates results. Some forget to convert between gallons and liters, causing chemical dosing errors. Others ignore attached spas, tanning ledges, or shallow shelves that add capacity.

Pool Volume FAQs

How many gallons are in a 12×24 pool?

A 12×24 pool with an average depth of 5 feet holds about 10,800 gallons. The formula is length × width × average depth × 7.5.

How accurate is an online pool calculator?

Online calculators are accurate for standard pool shapes when dimensions are entered correctly. Accuracy decreases with freeform designs or uneven bottoms.

Can I use pool volume to estimate heating costs?

Yes, pool volume directly affects heating cost. A larger pool requires more energy to reach the desired temperature and longer heating times compared to a smaller pool.

Why Use Our Pool Volume Calculator

Common Pool Sizes and their Volume

Here is the data of some of the common Above-Ground and Inground pool sizes, so that you can skip the calculations.

Rectangular Inground Pool Sizes

Average Wall Height
Pool Size	Gallons
12×24 Rectangular	10,800
16×32 Rectangular	19,200
16×36 Rectangular	21,600
18×36 Rectangular	24,300
20×40 Rectangular	30,000

Oval Inground Pool Sizes

Average Wall Height
Pool Size	Gallons
16×32 Oval	17,000
18×36 Oval	21,700
20×40 Oval	26,800

Grecian Inground Pool Sizes

Average Wall Height
Pool Size	Gallons
17×33 Grecian	19,700
17×37 Grecian	22,200
20×36 Grecian	24,300
20×44 Grecian	30,300

Kidney Inground Pool Sizes

Average Wall Height
Pool Size	Gallons
16×30 Kidney	14,900
16×34 Kidney	16,500
20×38 Kidney	20,200

Round Above-Ground Pool Sizes

	48″ Wall Height	52″ Wall Height
Pool Size	Gallons	Gallons
15′ Round	5,300	5,800
18′ Round	7,600	8,300
20′ Round	9,400	10,200
24′ Round	13,600	15,300
27′ Round	17,200	18,600
28′ Round	18,500	20,000

Oval Above-Ground Pool Sizes

	48″ Wall Height	52″ Wall Height
Pool Size	Gallons	Gallons
11×25 Oval	6,500	7,000
15×25 Oval	7,800	8,400
15×30 Oval	8,900	9,600
18×33 Oval	10,600	11,500
18×38 Oval	14,000	15,200

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