Pools come in all shapes and sizes so you can select the best one for your yard and how you want to use it. Whether you already have a pool, or are thinking about getting one, we have answers to all of your questions about pool size.

What Is A Good Size Swimming Pool For You?

When you are thinking about installing a pool, it can be hard to decide what size is right for you. Of course your budget, how much space you have to work with, and what you will use the pool for, will help you make the decision.

Most people are interested in a pool for recreation and relaxation with friends and family. In that case, consider how many people will use the pool and how often they will use it in order to determine what size is right for you.

Maybe you are the athletic type and want a pool to use for sports. If you love to swim laps or play water polo at your local community pool, you might be wondering how you can bring the practice home. For reference, an Olympic swimming pool is 164 feet (50m) long, 82 feet (25m) wide, and 6.5 feet (2m) deep. It holds over 660,000 gallons of water! A water polo pool is 98 feet (30m) long, 65 feet (20m) wide, and 6.5 feet (2m) deep. Obviously, you aren’t going to install an Olympic sized pool or an official water polo pool at your house, but there are some options. If you have a large yard, you might have room for a 30-40 foot long lap pool, which is considered sufficient for getting a good workout. And 6.5 feet of depth is certainly an option for most backyard pools.

How To Calculate Pool Capacity

If you already have a pool, but you don’t know how many gallons of water it holds, it is important to find out. To calculate the capacity of your pool, use one of the following formulas:

  • Rectangular pool: Length x Width x Average Depth x 7.5 = Total Gallons
  • Oval Pool: Long Diameter x Short Diameter x Average Depth x 5.9 = Total Gallons
  • Circular Pool: Diameter x Diameter x Average Depth x 5.9 = Total Gallons

Now that you know the capacity of your swimming pool, you can answer many common questions, including:

How long does it take to heat a pool?

Of course many outside factors will affect how long it takes to heat your pool, including the outside temperature and the type of pool heater you have, but here is a general formula:

Gallons of water x weight per gallon (8.33lbs) x degrees desired ÷ BTU output of the heater = hours to heat a pool

You can also heat your pool with the power of the sun. Results will vary based on the type of solar heater you use, and whether you decide to use a solar pool cover.


How long does it take to fill a pool?

If you are having water trucked in and dumped into your pool all at once, of course this process will be quick. But if you are planning to fill your pool using your garden hose, it will take many hours. Assuming that an average ½ inch garden hose delivers 540 gallons of water per hour, it would take around 18.5 hours to fill a 10,000 gallon pool (pool capacity ÷ fill rate per hour = hours to fill pool). When you are filling a pool for the first time, it is important to get the water balanced. A high quality start-up kit makes this process super simple

How much chlorine and other chemicals should I add to my pool?


There are many different chemicals that are required in a pool to keep the water clean and balanced for optimal clarity. You can calculate the amount of chlorine or bromine, algaecide, clarifier and stabilizer that you need to add to your pool when you have a good pool water test kit and you know your pool’s capacity.

Pool size is an important factor to consider, whether you already maintain your own pool or are just doing your preliminary research. If you have any questions about your pool, or need help selecting the right size pool for your home, Doheny’s team of experts is here to help. Give us a call today at 800-574-7665 or visit us online at doheny.com.