The only air purifiers for large rooms we recommend

Sadly, most “best air purifier” lists you will find ranking on Google or YouTube are nothing more than the latest list of the best-selling devices, regardless of whether they will be suitable for large spaces.

In fact, most air purifiers are designed for small spaces (up to 300 sq. ft.), so the units recommended by big media publishers generally don’t pack the power needed to clean very large rooms. That can lead you to buy an underpowered air purifier that won’t be effective at keeping the air clear of pollutants because it just can’t clean the air fast enough.

For large rooms, you need an air purifier with a high clean air delivery rate (or CADR) to provide the recommended 4.8 air changes per hour needed to help reduce the level of particulate matter in the air. That is why all our picks for large spaces have a high CADR.

Of course, we didn’t stop there.

Before we put together the list you’re about to read, we tested the air cleaning performance of every air purifier by burning an incense stick in our test room and using two PurpleAir laser particle sensors to track how long each unit needed to remove the smallest particles (PM1) from the air. And that was just the first of many tests…

But we don’t just test our devices; we live with them.  Our home is full of air purifiers, so we can uncover things that testing in isolation won’t reveal — from how easy it is to clean the pre-filter to how reliable the auto-mode or the app is.

Based on our first-hand data and experience living with these devices, these are the best large-room air purifiers available to buy right now.

Staff picks: The best air purifiers for large rooms

If you don’t have time to read through my full article, scroll through the table below to see my picks.

Now, if video is your thing, you might prefer to watch the video version of this article:

I’ve chosen air purifiers with individual strengths because we all have different needs. Whether it be performance, sound, size or budget, this guide has something for everyone.

1. The best overall: Smart Air Blast Mini

A BIG air purifier with a huge fan and filter that still manages to clean the air quietly—the best-performing air purifier for rooms up to 703 sq. ft.

The CADR for this air purifier is 435 CFM (740 m3/h). Smart Air recommends it for spaces of 915 sq. ft. (85 m2), but based on our calculations, you will get 4.8 air changes in rooms up to 703 sq. ft. When we tested it running at top speed, it cleaned our test room in 12 minutes, which was quicker than any other device we had tested:

What is even more impressive is that the Blast Mini still managed to clean our test room in 16 minutes when running at its lowest fan speed which produced less than 45 dB of sound. This air purifier truly blew my mind.

Sure, the PC fan DIY kit air purifiers still provide quieter operation, but for pure air cleaning power at sub-45 dB, the Smart Blast Mini MKII is the device to beat:

Behind the stylish front cover of the Blast Mini, you will find an incredibly powerful fan and a huge, long-life H13 HEPA filter. It is worth mentioning that the Blast Mini doesn’t have an activated carbon filter as standard, so if you are looking for an air purifier to help tackle unwanted smells or VOCs in a large room, I highly recommend you spend a little extra to add a carbon filter.

There are no special bells and whistles on the Blast Mini like auto mode, air quality monitor or touch-screen control. Founded by people who weren’t happy with the cost of air purifiers, Smart Air set out to produce high-performing, low-cost, no-thrills units that do their job really well. That is why their devices don’t have sensors or any smart features, so I use my Blast Mini connected to our Philips Hue system to run it on a schedule that works for our home.

➜ Read our full review

2. The best value for your money: AirFanta 3Pro

At $149.99, the AirFanta 3Pro is the most affordable high CADR air purifier on the market today for spaces up to 671 sq. ft.

The design of the AirFanta 3Pro is inspired by the Corsi-Rosenthal box: a base at the bottom, a custom-made HEPA H11 filter on each side and an array of powerful PC fans on top. At its highest fan speed, it has a CADR of 436 CFM, so it can provide 4.8 air changes per hour in rooms up to 681 sq. ft. 

Looking at those figures, you can probably understand why the 3Pro earned a spot on this list. Try finding a traditional HEPA device with a CADR north of 400 cfm for less than 150 bucks!

When running at its top speed, the 3Pro cleaned our 728 cubic ft. test room of all traces of PM1 particles in just 14 minutes with HEPA filters only and 18 minutes with HEPA + carbon filters.

When calculating the total running costs associated with running an AirFanta 3Pro at full speed every day, you can expect to spend $125.23 per year—this aligns with the running costs you will see with other popular air purifiers:

You will not find any other air purifier with a CADR above 400 that you can bring along with you wherever you go. This makes the AirFanta an excellent choice for events and shows.

Like the Smart Air device, it doesn’t have any smart features, but the power control allows you to find a sound level you’re happy with. For those wanting to clean a large room for the best bang for the buck, the AirFanta 3Pro is our top choice.

➜ Read our full review

3. The quietest option: CleanAirKits Luggable XL

With seven SickleFlow 120 PC fans and two Filtrete 20×25 MPR1900 filters, this is the quietest air purifier for rooms up to 485 sq. ft.

The Luggable XL is another air purifier powered by PC fans that was also inspired by the Corsi-Rosenthal Box. While traditional CR boxes use box fans and work well, they also take up a lot of floor space and run loud. CleanAirKits improved on that design by bringing together a combination of powerful PC fans with HVAC filters, allowing the Luggable XL to clean the air effectively without excessive noise or energy usage.

We went with the 7 Sickleflow versions of the Luggable XL, which costs $227 as a kit without filters and $299 fully assembled. This version has an estimated CADR for dust of 323 CFM and in our testing, it cleared all PM1 pollutants inside our 728 cubic ft. test room in 20 minutes:

20 minutes is very good performance, matching what we saw with popular retail units like the Winix 5500-2 (20 minutes), the Levoit Vital 200S (18 minutes) and Philips 3000i Series (18 minutes). However, the thing that impressed me the most was the level of sound we recorded with our sound level monitor:

Even though upfront costs can get a bit high depending on what options you go with, the CleanAirKits Luggable XL will be much cheaper in the long term thanks to the use of HVAC filters and the lower energy usage from the PC fans. 

So, for those who want a super quiet air purifier for a large room, then look no further than the Luggable XL as it can provide five air changes per hour in rooms up to 485 sq. ft. while generating 38.8 decibels of noise.

➜ Warch our video review

4. The best for workshops and renovations: AlorAir CleanShield HEPA 550

An powerful air scrubber for those wanting to remove dust and other particles from large workshops or areas in renovation up to 800 sq. ft.

If you want a device that can handle dust from large construction areas or gases inside big workshops, then consider this beast. The CleanShield HEPA 550 is suitable for 800 sq. ft. and has a reported CADR of 550 CFM. You can even daisy chain three of these devices together for a total combined airflow of 1650 CFM. 

The AlorAir CleanShield HEPA 550 can quickly remove particles and gases in large spaces thanks to its combination of filters: You get one layer of HEPA + activated carbon, and then another layer with a MERV 10 filter for larger particles. 

When we tested it in our test room, all PM1 particles were reduced to zero in a speedy 16 minutes. This landed the Alorair Air Scrubber 550 at the top of our leaderboard for air cleaning performance – but it doesn’t come cheap at $497 and it is super loud:

To be clear, I wouldn’t use this like a standard air purifier. But for those who want something durable for large spaces to deal with renovation pollution, construction dust or workshop fumes, the the AlorAir CleanShield HEPA 550 is one to consider.

5. The best DIY option: Corsi-Rosenthal Box

A DIY air purifier for those who don’t want to buy another device for their homes that will be effective in rooms up to 680 sq. ft.

If you already have a box fan somewhere at home, you might be able to build an air purifier powerful enough for spaces as large as 680 sq. ft. I’m talking about a device that went mainstream during the first wave of the COVID-19 pandemic: the Corsi-Rosenthal box.

The brainchild of Dr. Richard Corsi and Jim Rosenthal, this do-it-yourself unit uses the basic principle of what an air purifier is: a fan and a filter. The CR box consists of four (or five) HVAC filters attached to a box fan using tape. There are no fancy functions or features, auto mode or air quality sensors, which can be a con or a pro, depending on your opinion. 

This is a great option if you need an air purifier right now—even the EPA has produced a study on DIY filters and found the Corsi-Rosenthal box to have the highest level of cleaning power for dealing with wildfire smoke. The very best design uses five filters, a cardboard shroud and has legs. We haven’t tested this version yet but we did test two other configurations.

The CR box with four MERV 13 filters and no shroud cleaned our test room in 32 minutes:

And the CR box with four MERV 13 filters and a cardboard shroud cleared the air in 30 minutes, meaning that the shroud shaved off two full minutes at no extra cost:

So, for those wanting to build an air purifier suitable for large spaces with stuff they have around the house (or spending less than $100), then the Corsi-Rosenthal box is the best option.

➜ Read our full review

Other units we tested but don’t recommend for large rooms

• Austin Air HealthMate – A large, robust, American-made air purifier containing a filter packed with 15 lbs of activated carbon for dealing with VOCs. However, it didn’t have the cleaning power that we expected from a unit of this size. Our air cleaning performance test results show that it needed 37 minutes to clear all PM1 pollutants from the air in our small 728 cubic ft. test room — that is nearly the same amount of time it took the Levoit Core 300, which is a small device that you can place on the kitchen counter.

• Blueair Blue Pure 211+ – This was a strong contender for our guide. It’s powerful, comes with effective filters, looks really cool and is extremely easy to use. However, it didn’t make my list for one reason: you can’t disable its ionizer. I wrote about ionizer technology in depth here, but studies show that ionization produces harmful by-products, such as ozone and nitric oxide, that are not only harmful with people with respiratory conditions but can also interact with common household chemicals to generate new ultrafine particles.

• PuroAir HEPA 14 240 – Despite the manufacturers’ bold claims, the PuroAir 240 simply doesn’t clean the air effectively in large spaces. This air purifier needed 48 minutes to clear all PM1 particles from the air in our small test room, so it would take hours to clean the air of a large space. Plus, considering it’s priced at $159, this is an expensive device for this level of air cleaning power.
  
  

Wrapping up

Before we close this article, I want to talk about very large spaces—those close to 1000 sqft. 

When you’re trying to find a solution for spaces this large, you will find that even the Smart Air Blast Mini will not be powerful enough to provide enough air changes per hour.  Now, Smart Air does offer a large device called Blast, which is good for spaces of 1,300 sq. ft. and costs $929. 

But you also have the option of using multiple devices.

To work out the total power of multiple devices, all you need to do is just add their CADR together. 

You can use our CADR calculator to figure out how much CADR you need depending on the size of the room:

I hope you find what you’re looking for among the air purifiers I chose for large spaces. As always, let me know in the comments if you have any questions. Or email me directly if you need help finding a device that works for your specific situation.

Last update on 2024-12-08 / Affiliate links / Images from Amazon Product Advertising API