Pools, those shimmering bodies of water that offer a refreshing escape from the scorching heat of the summer, contain a secret that lies beneath their sparkling surface.

The purpose of this article is to examine the intriguing subject of swimming pool volume, including its meaning, calculation methods and practical applications.

Understanding swimming pool volume

To truly appreciate the importance of swimming pool volume, we must first grasp its definition and significance. Swimming pool volume refers to the total amount of water a pool can hold. According to the country where a pool was built, it is measured in gallons or cubic meters. Volume has an impact on swimming pool construction costs, but also on maintenance expenses.

Pool water volume calculation methods

There may appear to be a daunting task involved in calculating the volume of a swimming pool, but there is nothing to worry about! There are several methods available that make this process as easy as possible. One popular technique is to use geometric formulas based on the shape of the pool, such as rectangular, circular, or irregular. Additionally, advanced pool volume calculators and mobile applications have made it easier than ever to obtain accurate measurements of a pool.

Rectangular pool volume calculation

This calculator takes the pool’s length, width, and depth and calculates the volume of water it holds. The method is very simple: you multiply the length by the width to determine the surface area. Then, multiply this figure by the average depth to obtain the total water quantity. For example, for a pool with a length of 26 feet (ca. 8 m), a width of 13 feet (ca. 4 m) and a constant depth of 4.60 feet (1.4 m), the volume is 11,834 gallons (ca. 45 m³).

Volume calculation for circular pool

For round pools, things are a little more complicated.

  • First, you need to determine the radius of the pool by dividing its diameter in half.
  • Then multiply the radius figure by itself.
  • Then multiply the new figure by the value π (3.14).
  • Finally, multiply this new value by the average depth of the pool.

The formula is: (diameter/2)² x π x average depth = volume in gallons or cubic meters. 

So, for a pool with a diameter of 29 feet (ca. 9 m) and an average depth of 5 feet (1.52 m), the volume will be around 25000 gallons (ca. 95 m³).

Water volume calculator for free-form pools

When calculating the volume of an irregular-shaped pool, there are several methods available, depending on the complexity and shape of the pool. The most common method is to calculate the average length and average width of the pool. Then you multiply them to get the pool area. To get the volume, simply multiply the area by the depth or the average depth of the pool. For more complex shapes, you may need to use more complex calculations. There are also tools available online that can help you calculate the volume of an irregular-shaped pool.

Practical tips for measuring pool depth

Accurate depth measurement is essential for a reliable volume calculation. Use a sturdy tape measure and measure the depth at several points around the pool. Take into account differences in height due to slopes or steps and calculate an average depth.

Morana's advice 👇

Reduce your pool volume

A few gallons or cubic meters less water in your pool won’t spoil the pleasure of swimming. It doesn’t take much water to enjoy your pool — just 4.30 feet (1.31 m)!

Turn your excessively deep pool into a shallow one

It is easy to reduce the volume of an existing swimming pool. A professional can advise and assist you with the work involved, and the results will be real savings in water and chemicals.

Want help designing the pool of your dreams?

The Importance of Knowing the Volume of Your Pool

 To ensure that your pool is properly maintained and meets your needs, it is crucial to have accurate knowledge of its volume. Here are some reasons why knowing the volume of your pool is important:

Pool equipment selection

Selecting the right pool equipment and features requires an understanding of the volume of your pool. Knowing the capacity, for example, will assist you in selecting the appropriate size and power of pumps, filters, and heaters for your pool. As a result, your pool will have adequate circulation, filtration, and heating capabilities, leading to improved water quality and overall enjoyment.

Chemical balancing

Maintaining the chemical balance of your pool is essential to prevent health issues and extend the lifespan of the pool’s components. By knowing the volume of your pool, you can accurately calculate the necessary amounts of chemicals required for water treatment. This ensures that you apply the correct dosages, minimizing the risk of skin irritation or damage to the pool’s surfaces and equipment.

Pool maintenance and cleaning

Understanding the volume of your pool is essential for efficient pool maintenance and cleaning. By knowing the amount of water in the pool, you can calculate the proper frequency of backwashing, vacuuming, and chemical treatments. This ensures that your pool remains clean and free from debris, reducing the need for extensive cleaning efforts.

Safety and compliance

 Understanding the water capacity of your pool is crucial for ensuring the safety of swimmers and preventing accidents. By knowing the volume of your pool, you can accurately calculate the necessary safety features such as depth markers, barriers, and lifeguard staffing requirements. Additionally, this knowledge helps to comply with local regulations and codes related to pool design and maintenance.

What's the point of reducing swimming pool water volume?

In this section, we will explore the importance of reducing pool water volume and the numerous benefits it brings. Taking steps towards water conservation, energy efficiency, and cost savings can have a significant impact on both your wallet and the environment. 

Environmental impact

Large pool water volumes can have a notable environmental impact. Excessive water usage puts a strain on local water supplies, especially in drought-prone areas. By reducing pool water volume, you actively contribute to mitigating this strain and reducing the overall environmental footprint associated with pool ownership.

Cost savings

Reducing the volume of pool water can result in substantial cost savings. In the case of a smaller pool volume, less water is required for its filling or refilling. Additionally, fewer chemicals are required for treatment and maintenance.

Moreover, by minimizing the energy required to operate your pool, you can reduce your utility bills significantly. Over time, these savings can add up and make a significant impact on the overall costs of pool ownership.

Pool maintenance

Maintaining proper water chemistry in a pool with a large volume of water can be challenging and time-consuming. By reducing pool water volume, you make pool maintenance more manageable.

It becomes easier to achieve and maintain the ideal water balance, ensuring a safer and healthier swimming environment for you and your loved ones.


In conclusion, pool volume calculation is an art that every pool owner should master. Precision pool volume measurement allows for efficient chemical dosages, effective filtration, and overall better pool maintenance. With an understanding of the impact of pool volume, owners can have a refreshing, well-balanced swimming experience.