Top performing air purifiers for wildfire smoke (+ DIY units)

If there's wildfire smoke outside, do not to leave your home and build (or buy) an air purifier — our guide will teach you more.
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As the tinted red skyline of New York City showed the world during Canada’s wildfire season, even areas that are not at high risk of wildfires can be impacted many hundreds of miles away. In fact, Americans breathed more wildfire smoke in the first eight months of 2023 than they had during any previous full year since 2016. 

stanford study cumulative PM2.5 for americans in 2023

Wildfire smoke generates tiny particulate pollution (PM1, PM2.5 and PM10), odor (VOCs), and other gasses. The most dangerous pollutants are tiny particles measuring 1-10 microns, which are small enough to pass through lung tissue and get into the bloodstream. The good news is that high-performing air purifiers with the right filters can remove these particles from the air before we breathe them into our bodies.

My recommendations today are based on more than 90 air purifier tests, where we assessed the air cleaning performance of different brands and models to find the units powerful enough to quickly clear wildfire smoke from the air without breaking the bank.

How we test air purifiers

Read our full testing methodology.

Let me point out that I included two air purifiers that you can build at home: the Corsi-Rosenthal Box and a simple fan+filter DIY air purifier. I did this because wildfire smoke can accumulate very quickly, so the best solution is to get a device to clean your air ASAP.

If you suffer from regular issues with indoor air quality or live in an area prone to wildfires, investing in a high-performing air purifier will make the most sense in the long term. But not everyone has the means to buy a powerful air purifier, so these DIY alternatives are definitely worth considering if that’s you.

HouseFresh picks: The best air purifiers for wildfire smoke

Below, you’ll find a more detailed yet compact overview of each unit in my shortlist for this type of smoke pollution.

DIY OPTIONBUDGET OPTIONLARGE SPACESSMALL SPACES
Corsi-Rosenthal boxAirFanta 3ProSmartAir Blast MiniLevoit Vital 200S
Corsi RosenthalAirFanta 3Pro CornerBlast Mini MKII Kids RoomLevoit Vital 200S Bedroom
Air cleaning speed30 minutes14 minutes12 minutes18 minutes
CADR274 CFM430 CFM435 CFM242 CFM
Filter techMERV 13True HEPA H11 + carbonH13 HEPA filter + carbonBonded particle + carbon
Filter life6-12 months6-12 months13 months12 months
Max room size680 sq. ft.671 sq. ft.703 sq. ft.375 sq. ft.
Sound levels49-60 dB36-56 dB44-56 dB38-57 dB
Long-term running costs$110.88 / year$125.23 / year$311.89 / year$127.94 per year
Upfront cost$85.00$159.99$599.00$189.99

Read on to learn more about each of my top picks. Make sure to scroll down to find out which air purifiers I definitely don’t recommend for wildfire smoke.

Right, without further ado, these are my recommendations.

1. DIY option: Corsi-Rosenthal Box 

For those reacting to the immediate threat of wildfire smoke, you can build your own Corsi-Rosenthal Box with a box fan, four HVAC MERV 13 filters, cardboard and duct tape.

Corsi-Rosenthal box in a corner

The main reason this air purifier is the one on my list is that it can be built using items you already have in the home. Engineers Richard Corsi and Jim Rosenthal popularized the Corsi-Rosenthal box during the COVID-19 pandemic to reduce the viral particles in indoor environments. While designed for airborne viruses, the CR box can still help remove the dangerous tiny particles created by wildfire smoke. 

What we really like

You can build your own Corsi-Rosenthal box with four HVAC filters, a box fan, some cardboard and tape. Easy and affordable.
It is relatively easy to put together and can be an activity to do with kids at home.
Despite being a DIY air purifier, it cleaned our test room in 30 minutes — that’s more than twice as fast as the average speed across all units we tested.
It’s highly customizable. You can choose the fan and filters you want to use to build it.

What we think could be better

There is no option to add activated carbon, so the CR box will only be able to clear the air from particles but it won’t be effective against the odors and gases generated by wildfires.
It has a large footprint, so it will take up a fair share of space.
Box fans can be loud. The noise levels vary from fan to fan, so make sure to find one that is comfortably quiet.
To change the filters, you’ll need to remove the duct tape and re-tape the new ones. Make sure to have MERV 13 stock available during wildfires, as the filters will need regular replacement.

The Corsi-Rosenthal box does require you to put it together, but it’s relatively simple, and while it takes up a large amount of floor space, its performance at removing pollutants is worth it. Be sure to use HVAC filters that are at least MERV-13. I used the BNX Tru filters MERV 13 and the Hurricane 20-inch box fan in our CR Box, but you can use any 20-inch box fan and filters as long as they are MERV-13 or higher grade.

As with all the air purifiers we review here at HouseFresh, we tested our 20×20 Corsi-Rosenthal box in the same 728-cubic-ft test room where we have tested nearly 100 air purifiers to date. The CR box impressed me: it was able to bring down the levels of PM1 to zero in 30 minutes. This is eight minutes faster than the $850 Austin Air HealthMate HM400 and 14 minutes faster than the Intellipure Compact device used in NYC schools.

HouseFresh rating:★★★★☆
Time to clean our 728 cubic feet test room (with the device running at top speed):30 minutes (with a cardboard shroud)
Air purifier technology:MERV 13
Recommended room size (5 air changes per hour):411 sq. ft.
Clean air delivery rate (CADR):Estimated: 274 CFM 
Dimensions (in inches / in cm):20L x 20W x 20H inches (50L x 50W x 50H cm)
Weight (in pounds / in kg):10 lbs (4.5 kg)
Filter life:6-12 months
Noise level in decibels (measured from 3 ft. away with a sound level meter):Speed 1: 49 dB
Speed 2: 55.1 dB 
Speed 3: 60.7 dB
Electricity consumption in watts (recorded with an electricity usage monitor):Standby mode: 0 kWh
Speed 1: 40.5 kWh
Speed 2: 44.5 kWh
Speed 3: 46.7 kWh
Estimated running cost (electricity consumption + official filter replacement):$110.88 per year
Cost per CADR cfm (based on dust CFM as reported by AHAM):$0.29
Manufacturer’s warranty:n/a
Country of manufacture:China

Read our full review

DIY fan and filter air purifier

Air purifiers are essentially just a fan and a filter, and that is exactly what this DIY air purifier is.

You can read our full guide and review of this simple DIY Air Purifier, but in simple terms, you just attach a MERV-13 filter to a box fan and voilà.

In terms of air cleaning performance, it needed more than twice as much time to clear our small test room of PM1 smoke particles but when dealing with wildfire smoke, this simple DIY device is most definitely better than having no air purifier at all.

Alternatively, you can look for a ready-made fan and filter device in the Lasko AirFlex 2-in-1. A pro tip for those who choose for this option: we swapped the Lasko filter for a 3M Filtrete 20×20 filter and this doubled its air cleaning performance:

2. Best budget option: AirFanta 3Pro

At under $150, the AirFanta 3Pro boasts outstanding air cleaning performance thanks to four 140mm PC fans — plus, it can cover areas as big as 671 sq. ft.

AirFanta 3Pro on bench

Use the discount code HOUSEFRESH for 5% off when buying directly from AirFanta.

The design of the AirFanta 3Pro is inspired by the Corsi-Rosenthal box (above): a cube with a filter on each side, fans on top and a base at the bottom. But here’s the main difference: the 3Pro uses four PC cooling fans instead of a regular box fan.

The AirFanta 3Pro comes with four low-resistance H11 filters, which quickly remove smoke particles from the air with each pass. I recommend you to choose the filters that combine HEPA + activated carbon to clear your air from particles AND the gases and odors that come with wildfire smoke.

What we really like

With an estimated CADR of 430 CFM and a price of $149.99, this is the most affordable high CADR air purifier on the market today.
It offers outstanding air cleaning performance — it cleared all incense smoke from our test room in 17 minutes, which is only two minutes slower than the fastest air purifier we have tested.
It is easy to build in just a few minutes. Once disassembled, you can fit it inside a carry-on bag or small suitcase to take with you.
It is a small 12.6×12.6 inches (32×32 cm) box, so it will fit most spaces — especially when compared to a Corsi-Rosenthal box.

What we think could be better

Running at 56.3 dBA, it is louder than other PC fan powered-air purifiers we have tested when running at full speed, but it is also A LOT cheaper.
It is less energy-efficient than other (much more expensive) PC fan air purifiers.

Unlike other air purifiers on this list, the AirFanta 3Pro is quite small, and there is a reason for that: once disassembled, the 3Pro is the only high-CADR air purifier that can fit inside a carry-on bag. This can be particularly handy during wildfires, as you will be able to pack your air purifier to bring it with you wherever you go.

HouseFresh rating:★★★★★
Time to clean our 728 cubic feet test room (with the device running at top speed):17 minutes
Air filtration technology:True HEPA H11
Recommended room size (4.8 air changes per hour):671 sq. ft. 
Clean air delivery rate (CADR):Estimated: 430 CFM
Dimensions (in inches / in cm):12.6D x 12.6W x 12.6H inches (32D x 32W X 32H cm)
Weight (in pounds / in kg):7.7 lbs (3.49 kg)
Filter life:6 – 12 months
Noise level in decibels (measured from 3 ft. away with a sound level meter):3.63 volts: 36.1 dB
4.19 volts: 36.9 dB
5.24 volts: 39.7 dB
6.54 volts: 43.3 dB
7.44 volts: 46.7 dB
8.56 volts: 49.1 dB
12.6 volts: 56.3 dB
Electricity consumption in watts (recorded with an electricity usage monitor):43.23 watts
Estimated running cost (electricity consumption + official filter replacement):$125.23 per year
Cost per CADR cfm (based on dust CFM as reported by AHAM):$0.35
Manufacturer’s warranty:1 year
Country of manufacture:China

Read our full review

Watch our video review

3. Best for large spaces: Smart Air Blast Mini

A fast and quiet powerhouse that can achieve five air changes per hour in spaces as large as 675 sq. ft.

Smart Air Blast Mini MKII in kids room

Speedyness is key when there’s a wildfire nearby. At $650, the Blast Mini is not as affordable as the AirFanta 3Pro, but it comes with such a powerful fan that it bested all 94 units we tested so far, completing our particle removal test in just 15 minutes. 

The massive size of the medical-grade HEPA filter in the Blast Mini is perfect for capturing the fine particles (PM2.5) produced by wildfires. Although the activated carbon filter is not included in the standard purchase, I strongly recommend getting one, even if it means an extra $90. The 2.6 lbs of loose-fill carbon will remove VOCs and gasses produced by wildfires, and it will also help with the pervasive smoke odors.

What we really like

For such a powerful unit, the Blast Mini noise output tops at 56 dB when running at full speed. A significant advantage, considering during wildfire season you’ll be running the air purifier 24/7. 
It comes with one of the largest H13 HEPA filters available on the market, which can also last longer than the average (13 months).
Super simple to operate, with no more than a dial to choose between three fan speed levels.
Top-notch lockable, metal castor wheels to move around in any direction.
It is made of metal, which makes it a more sustainable and long-lasting choice than most plastic air purifiers.

What we think could be better

A powerful fan comes at a cost. This power-hungry unit will add $130 to your annual energy bill.
Filter replacements don’t come cheap, costing $236.99 per year if you get both HEPA and activated carbon filters.
It’s not exactly mini, but rather a big, heavy unit weighing 59 lbs. However, it comes on four caster wheels that make it easy to move around the house.

The reliable Blast Mini doesn’t just stand out for its air cleaning speed and large filters. It is also designed for large spaces and is able to provide five air changes per hour in rooms as big as 675 sq. ft. It has a high price tag but if you are looking for outstanding air cleaning power, then the Blast Mini won’t disappoint.

HouseFresh rating:★★★★★
Time to clean our 728 cubic feet test room (with the device running at top speed):15 minutes
Air purifier technology:H13 HEPA filter (and optional activated carbon filter)
Recommended room size (4.8 air changes per hour):703 sq. ft.
Clean air delivery rate (estimated CADR):435 CFM
Dimensions (in inches / in cm):22.6L x 13W x 24.8H inches (57.5L × 33W × 63H cm)
Weight (in pounds / in kg):59 lbs (26.8 kg)
Filter life:13 months
Noise level in decibels (measured from 3 ft. away with a sound level meter):Speed 1: 44.9 dB
Speed 2: 51.2 dB
Speed 3: 56.3 dB
Electricity consumption in watts (recorded with an electricity usage monitor):Standby mode: 0 watts
Speed 1: 51.9 watts
Speed 2: 87.4 watts
Speed 3: 122.7 watts
Estimated running cost (electricity consumption + official filter replacement):$285.29 per year
Cost per CADR cfm (based on dust CFM as reported by AHAM):$1.38
Manufacturer’s warranty:1 year
Country of manufacture:China

Read our full review

4. Best for small spaces: Levoit Vital 200S

This is our top recommendation for those looking for a smart air purifier with particle and carbon filters for under $200.

Levoit Vital 200S in our living room

You don’t need ultra-powerful air purifiers for smaller spaces. However, I strongly recommend choosing a unit with a minimum CADR of 200 CFM, even more so if you need to deal with wildfire smoke pollutants. That is why I am recommending the Vital 200S as it has a smoke CADR of 242 CFM and will be able to clean the air five times per hour in rooms as large as 395 sq. ft.

The Vital 200S comes with a removable pre-filter (which makes washing far easier and can extend the filter’s lifespan for up to 12 months), and a bonded particle and activated carbon filter. The 200S is also powered by an energy-efficient yet powerful fan, making it possible for it to complete our particle removal test in 23 minutes, which is three minutes faster than the popular Coway Airmega AP-1512hh and seven minutes faster than the $400 Alen BreatheSmart 45i.

It’s worth noting that the filters are no longer advertised as True HEPA after Dyson complained to the BBB. Instead, according to Energy Star, it uses a HEPA-type main particle filter. However, as we’ve seen with the outstanding performance of Corsi-Rosenthal box and the CleanAirKits Luggable XL-7 (both of which use MERV 13 filters), HEPA filters are not a requirement for optimal particle filtration.

What we really like

Outstanding cleaning power for under $200, with an efficient $ per CADR ratio and affordable long-term running costs.
Despite being budget-friendly, the Vital 200S features a top-tier control panel with air quality readings and a light detection mode to react to ambient light.
It runs quietly at its top speed (57 dB). This is Turbo mode, or Speed 4, which is not a common feature in budget units like this one. At Speed 3, the noise output lowers to 53 dB (equal to the sound of a quiet suburb).
It is a compact unit with a reduced footprint, so it’s easy to find a spot for it in small rooms. It is as sleek as a budget-friendly air purifier can get.
It comes with smart features such as an air quality indicator on-screen, auto-mode and smartphone connectivity.

What we think could be better

It is more expensive than small air purifiers, such as the Winix A230, but it will give you enough CADR to achieve safe indoor air quality levels in small rooms during wildfires.
The air quality sensors need periodic cleaning (every two months) to work properly. Dust and particulates accumulated in the sensors will affect this unit’s auto-mode performance.
Levoit advertised medical-grade HEPA filters for this unit at launch, but they removed all mentions of HEPA after being challenged by Dyson. Not great.

Intensive use during wildfires won’t break the bank, if you consider the long-term running costs: it will cost less than $130 a year to run the Vital 200S 24/7, including the added cost to your electricity bill and the price of filter replacements.

HouseFresh rating:★★★★★
Time to clean our 728 cubic feet test room (with the device running at top speed):23 minutes
Air purifier technology:Bonded particle and activated carbon filter
Recommended room size (4.8 air changes per hour):375 sq. ft. (5 ACH)
Clean air delivery rate (CADR):Dust: 263 CFM
Smoke: 242 CFM
Pollen: 240 CFM
Dimensions (in inches / in cm):15.6D x 8.5W x 19.8H inches (39.3D x 21.5W x 50.2H cm)
Weight (in pounds / in kg):13.2 lbs (5.9 kg)
Filter life:12 months
Noise level in decibels (measured from 3 ft. away with a sound level meter):Speed 1: 38.3 dB
Speed 2: 41.9 dB 
Speed 3: 53.8 dB
Speed 4: 57.7 dB
Electricity consumption in watts (recorded with an electricity usage monitor):Standby mode: 0.97 watts
Speed 1: 5.71 watts
Speed 2: 8.01 watts
Speed 3: 31.96 watts
Speed 4: 44.55 watts
Estimated running cost (electricity consumption + official filter replacement):$96.82 per year
Cost per CADR cfm (based on dust CFM as reported by AHAM):$0.72
Manufacturer’s warranty:2 years
Country of manufacture:China

Read our full review

Watch our video review

Only three minutes slower than the Blast Mini, the Core 600S will remove wildfire smoke from your home quickly for just $299. It has a high CADR for the price – 410 CFM overall and 377 CFM for smoke — and still boasts a solid amount of smart features usually seen in similarly powerful units that are twice as expensive.

Like most high-performing units, the Core 600S is big. Inside, you’ll find Levoit’s three-in-one filters, featuring a pre-filter, a large particle filter and, if you opt for the Smoke Remover filter, 0.79 lbs of pelletized activated carbon. Be aware, though, that the Core 600S needs filter replacements every six months.

Our Levoit Core 600S in our front room

For those looking for cost-effective, high-quality air purification for spaces that the Vital 200S will struggle in, the Core 600S is a solid option:

What we really like

It is the most affordable option for large spaces: for $299, the Core 600S can perform 4.8 air changes per hour in areas as big as 584 sq. ft.
It completed our speed test in only 15 minutes. You get similar results with units like the Levoit EverestAir ($500) or the AirDoctor 3000 ($519).
It tracks PM2.5 levels in your home, with a numeric display on the control panel (not just the regular color-coded indicator) and the app – which also showcases PM2.5 levels.
It only weighs 13.70 lbs, so it’s not too heavy to move between rooms.

What we think could be better

At top speed, it will get a tad loud. The Core 600S’s 61 dB noise output is equivalent to the sound of a normal conversation.
The air quality sensor is at the back of the unit, so it won’t work accurately if the unit is placed too close to a wall.
While the three-in-one filter is straightforward to replace, a removable pre-filter would be a better option for cleaning.

Four other solid air purifiers that didn’t make the cut

If none of the options above seem like the right fit, consider the devices in this section.

We have thoroughly tested and reviewed 94 air purifiers (and counting) so when we shortlisted our picks for this list, we had to make some tough cuts. Below I’ll tell you about three devices that are worth considering as well.

IQAir Healthpro Plus Entrance

IQAir HealthPro Plus

The HealthPro Plus has been in the market since the 90s and it’s still one of the most recommended air purifiers due to its powerful fan, HyperHEPA filter and impressive gas filter with 5 lbs of activated carbon and zeolite.

These features make this device an excellent choice for wildfire smoke but the reason why I didn’t include it in my short list is that this is an expensive option for the vast majority of people. The HealthPro Plus comes with an upfront cost of $949.99, plus an additional $300 per year in electricity and filter replacement costs.

That said, if budget is not a concern to you, then the IQAir HealthPro Plus is a solid air purifier that will be able to clear your air from both particles and the VOCs associated with wildfire smoke thanks to its combination of high quality filters.

Levoit EverestAir Front Design

Levoit EverestAir

The EverestAir is the top of the range for Levoit air purifiers and is one of the fastest (16 minutes) air purifier we have tested — the EverestAir reached PM1 zero in our 728 cubic feet test room in just 16 minutes, which is just one minute slower than the Smart Air Blast Mini.

It comes with a removable pre-filter, a high quality HEPA-like particle filter and pelleted activated carbon. It also has an in-built air quality sensor, auto-mode, adjustable vents, an LED air quality indicator, and smartphone connectivity.

The EverestAir comes with all the bells and whistles, but as with the IQAir above, I left it out because it is quite expensive at $499.99.

Winix 5500 2 TV Room

Winix 5500-2

This is a reliable air purifier with a washable pre-filter, a washable pelleted activated carbon filter and a True HEPA filter.

The 5500-2 cleaned our test room in 23 minutes, which is the exact same time it took the Levoit Vital 200S. The difference, however, is that the 5500-2 reached this result with PlasmaWave enabled, which is Winix’s ionizer technology.

For those looking to keep a room up to 364 square feet clean, the 5500-2 is definitely worth of your consideration. I opted for the Vital 200S instead because it offers the same performance for a cheaper price.

Smart Air SA600 Bedroom

Smart Air SA600

The Smart Air SA600 has two sets of removable pre-filters, HEPA H13 filters and activated carbon filters, two at each side of the device. This combination of filters paired with a powerful fan motor allowed the SA600 to clear the air in our 729 cubic feet test room in 24 minutes, which is just one minute slower than the Vital 200S.

All of this means that the SA600 is an excellent option for dealing with wildfire smoke, as it comes at a good price ($279.95). However, the yearly running costs are higher than most devices ($198.02) due to the use of twice as many filters. That’s why I didn’t shortlisted it.

Other units we tested but don’t recommend for wildfire smoke

If you can’t find what you’re looking for in the list above, email me before you end up buying a useless air purifier.

The five air purifiers below are on my do-not-buy list for those looking to clear the air from wildfire smoke:

  • Levoit Core 300 We love this budget air purifier, but it will be too underpowered to deal with a severe issue like wildfire smoke. You are much better off spending a little more for the Levoit LV-H133, which still has the same air-cleaning power as the Corsi-Rosenthal box.
  • Austin Air HealthMate This air purifier has a large amount of carbon (15 lbs), but its particle removal could be better considering its price of over $700. Wildfire smoke generates a ton of particulate matter, so you need better performance than the estimated 150 CFM, which took 37 minutes to remove all PM1 particles from our test room. 
  • Blueair Blue Pure 211+ Big media sites regularly recommend this air purifier, but it uses an ionizer that you can’t turn off that potentially can bring ozone into your environment. Considering that many non-ionizer units are available, there is no need to recommend this device for wildfire smoke.
  • AROEVE MK01 This popular cheap air purifier on Amazon could not fully clean our air of incense smoke even when we left it for 5 hours, so it would be useless with the particulates generated by a major wildfire.
  • PuroAir 240 – This air purifier is too underpowered to deal with wildfire smoke effectively. Not only that: you will find it discounted on Amazon all year round, but even with a discount, it is overpriced considering its performance.

Tips for protecting yourself from wildfire smoke

As we saw in New York in 2023, wildfire smoke can travel hundreds of miles from the source of the fire, so it’s important to be aware of the problem even if you don’t live in a high-risk zone. 

Using a DIY air purifier like the Corsi-Rosenthal box or buying a unit like the Smart Air Blast Mini is a great way to remove particulate pollution, but there are other things you can do to reduce the risk of wildfire smoke in your home.

  1. Seal Up: Wildfire smoke can pass through any gaps in your home, so seal up any spaces around windows and doors. Close any vents and outdoor intake dampers if you have a central AC. 
  1. Mask up: If you have to leave your home or use any rooms that don’t have air purifiers, then be sure to use an approved face mask and, if possible, also wear goggles as wildfire smoke can irritate your eyes. 
  1. Recirculate: You will still want to use your AC as temperatures will rise due to wildfire smoke, but you will want to enable the “recirculate mode” as this will mean it won’t pull polluted air from outside. 
  1. Run air purifiers 24/7: Wildfire smoke is a severe issue, so you will want to ensure that this smoke is continuously removed from your home air, as even when you seal windows and doors, it will still find a way to enter your home air.  Smart Air showed in their experiment that pollutants will increase when you switch your unit off, so be sure to keep it running until the wildfire risk is over.  

Tip

Be sure to check out our full guide for more tips on how to protect your home from wildfire, including how to clean up afterward.

Why should you trust me on this?

Most guides for air purifiers are written by freelance writers working for large media companies who say all the right things but often don’t perform in-depth performance tests. Instead, they often recommend air purifiers for commercial reasons, focusing solely on those units that will earn the highest affiliate commissions.

That is not us.

HouseFresh is 100% independent and not part of a large media company. We don’t do this to maximize our profits, we do it because we care about clean air. We are a husband and wife team, and buy the air purifiers we review with our own money to ensure we will be free to tell you which ones to avoid. We spend a lot of time gathering data on air purifier performance and share all our findings via our in-depth reviews.

If you have any questions that we haven’t covered in this wildfire smoke guide, then be sure to email me directly: danny@housefresh.com

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About the author

Danny Ashton

Danny is the founder of HouseFresh and has been writing about air purifiers since 2010. He is our lead tester and reviewer, and is also the human in front of the camera in our YouTube channel.

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