Photo of air purifiers ranging in sizeIn this post, we’ll show you how to determine the proper size you need for an air purifier.

This is an essential step when going through the process of deciding how to choose an air purifier that’s right for your needs.

Getting the right size air purifier is important because it ensures that the device will work most effectively inside your home.

The worst thing you can do is buy an underpowered air purifier and it not do a very good job at cleaning the air around you.

While you may think you’re breathing healthy air with it running, you most likely are not.

This guide will ensure that this situation doesn’t happen to you.

And to make things easier for you, we’ve put together a guide with the best home air purifiers here.

How to Choose the Right Size for an Air Purifier

First, Determine Where You Want to Place the Air Purifier

The most important factor when sizing an air purifier for your needs is to first determine where you want to place it.

Are you looking to purify the air within a single room, multiple rooms, or an entire house?

The answer to that question will help narrow down the optimal product choice for your application and make it much easier to compare air purifiers.

Next, Measure the Square Footage

After making this decision, the next step is to figure out what the square footage is for the space you want to purify.

If it is a single room, this step is quite easy.

All you have to do is use a measuring tape to take measurements of the two perpendicular walls.

This will allow you to determine the square footage for the room.

For example, a 10′ x 12′ room = 120 sq. ft.

If you want an air purifier that will cleanse the air for multiple connected rooms, then just measure the length and width of each room separately and add up the totals.

For example, if we have two adjoining rooms that are 120 square feet and 80 square feet, then the total square footage would be 120 + 80 = 200 sq. ft.

If you’re trying to size an air purifier for an entire house, the easiest method would be to look at the paperwork from when you bought the home.

That house plan should include the total square footage for your house.

If you can’t find this documentation easily, a simple method is to go outside and measure the length and width of your outside walls.

Then multiply that number by the number of levels your home has.

For example, if the outside square footage equals 1,200 square feet and you have a two-level home, this would be 1,200 x 2 = 2,400 sq. ft.

Finally, Match the Square Feet Rating on the Air Purifier to Your Room

Air purifiers come in all shapes and sizes and carry a maximum square footage rating on their specifications list.

If you’re looking to buy a product just to purify your bedroom or living room, it doesn’t make sense for you to buy a device that can clean a maximum of 3,500 square feet.

Not only will this product be too powerful for the room, but it will also cost you more money to operate.

It makes better sense to get an air purifier that is properly sized for your application.

If your room measures 150 square feet then get an air purifier that indicates a rating that is at or just above this number.

A 200 or 250 square feet rating would be just as efficient as one that measures 150 square feet exactly.

What you also don’t want to do is buy a product that doesn’t meet your particular area’s square footage.

Buying a device in order to save money that can only purify a room up to 80 square feet would be a waste of your investment, since it won’t be able to purify that large of a room.

If you’re trying to buy a product to purify your entire house, yet you can’t find a product that has a high enough square feet rating such as 5,000 square feet., you’ll need to make some compromises.

Instead of trying to purify your house with one device, it makes more sense to break your home up into small square footage sections and find a device that will work well for this size.

For example, if each level measures 1,500 square feet in a 3 level home, consider getting an air purifier that is sized to purify 1,500 square feet.

Then buy three of these devices and place one on each level of your home.

That way you can ensure that you are optimizing the efficiency of each device.

If you live in an apartment, things get a little bit easier and more affordable because you don’t have to purify as large of space.

Many apartments fall into a standard square footage size so finding a proper air purifier match is simple.

Check out our guide on the best air purifier for apartments here to find out what’s available.

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About David Morrison

David is an Air Quality & Comfort Technician. He has expert knowledge on the technology and design of air purification, air conditioning, and heating systems. His main role is to write content that helps people get the most value out of their air purifiers, air conditioners, and heating units. (See Full Bio)