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How to Determine the Size of Air Conditioner For Your Home or Office

Many potential buyers are perplexed by the size of the air conditioner they need. Well, worry no more because this guide will go over all of the intricacies and provide you with a clearer picture of what you may need for your property.

The first step in determining the correct air conditioner size is to determine the unit of measurement. The output of air conditioners in Australia is measured in Kilowatts (often expressed as kW). One thousand watts equals one kilowatt. 

Why is it crucial to get the correct size? Efficiency is the easy answer. Despite the fact that it may appear that bigger is always better, this is not the case with current air conditioners. Instead, air conditioners perform best when they are properly sized for the environment. An energy-efficient air conditioner is designed to run in cycles that cool your home slowly rather than quickly.


How to Calculate Your Air Conditioning Size

1. Using a formula

It’s quick and easy to estimate your air conditioning needs with a formula, but it’s also quite rough and ignores many of the crucial elements listed above. It’s a nice technique to acquire a rough concept of your requirements, but if you want a more precise knowledge, you should definitely utilize one of the other two ways first.

To figure out how much air conditioning you’ll need for your daytime living area, you’ll need to first figure out how big it is. The length and width of each room must be determined and multiplied. Then, for the total, sum the areas of each room together. This figure must be expressed in square metres.

What you do next is determined by the height of your ceiling:

  • For ceilings that are 2.4m high, multiply the day time living area (m²) by 150 (watts) 
  • For ceilings that are 2.7m high, multiply the daytime living area (m²) by 160 (watts)
  • For ceilings that are 3m high, multiply the daytime living area (m²) by 175 (watts)

These calculations will give you the number of watts you require, which you can convert to kilowatts by moving the decimal point three points to the left.

2. Using an online calculator

If you use an online calculator instead of the aforementioned method, you will get a more precise estimate, but you will have to consider additional aspects. Fairair ( has a handy calculator that may help you figure out how many kilowatts you’ll require.

3. Using the help of a professional

Having a professional come in and assess the air conditioning capacity that you will require for your home is the most precise approach to determine it. They have years of knowledge that they can draw on to provide you with the most accurate assessment of your air conditioning requirements. They will analyze each issue and work with you to ensure that you have the right size air conditioner for your home.

J&M Costa has a team of air conditioning experts that can help you determine the size and type of air conditioning that you need for your home or office. Contact us now to get a free quote. 

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