IQAir vs AirDoctor vs Blueair: Which Air Purifier to Buy

Standard HEPA is rated at 0.3 microns. IQAir's HyperHEPA and AirDoctor's UltraHEPA are sold on capture down to 0.003 microns, the ultrafine range that includes some mold fragments and combustion particles. Blueair Classic 480i uses HEPASilent filtration and is specified to 0.1 microns. That is a real step up from a box-store purifier, and it is not the same claim as IQAir or AirDoctor.

Room size is the second split. AirDoctor 5500 is the large-room machine, rated up to about 1,041 sq ft at two air changes per hour. IQAir HealthPro Plus and Blueair Classic 480i are bedroom machines. Putting a bedroom unit in an open kitchen-living space is the mistake these buyers make most often.

IQAir is mechanical filtration with no ionizer. Blueair's HEPASilent design combines mechanical filtration with an electrostatic stage. If you want zero ionizer hardware, IQAir is the one that states that plainly.

HealthPro Plus is the bedroom unit people buy when the problem is specific: mold history, chemical sensitivity, or a clinician who named ultrafine particles. Three stages: pre-filter, V5 gas and odor cartridge, HyperHEPA. The product data puts it at $899–$999 and about 28 lb. It is not a smart-home gadget. You set a speed and leave it.

Run it high for a short cycle when you enter the room, then drop to a low sleep speed. Filter changes land around 12–18 months depending on speed and how dirty the intake air is. Budget the replacement filters before you buy. They are a real share of the five-year cost.

Buy this if the purifier is for the room you sleep in and you already know you want the stricter particle claim. Skip it if you mainly want an app, a light bar, and coverage for a whole floor.

AirDoctor 5500 is the large-room counterpart. UltraHEPA is marketed at the same 0.003-micron class as IQAir, with a carbon/gas stage for formaldehyde and other VOCs, auto mode from a particle sensor, and a whisper setting around 30 dB. Price range on the product page is $629–$999, so street price sometimes overlaps IQAir and sometimes undercuts it by a few hundred dollars.

This is the unit for a living room that opens into a kitchen. One machine, high ceiling, people cooking. The sensor earns its keep here because load changes through the day. In a closed bedroom, that advantage shrinks and IQAir's simpler mechanical design is the cleaner spec.

Buy this if the square footage is the constraint. Do not buy it as a second bedroom unit when a Blueair would do that job for less.

Blueair Classic 480i is the quiet mid-price bedroom pick at $400–$600. HEPASilent is specified to 0.1 microns, with carbon for odors, an air-quality sensor, and a low speed around 32 dB. For pollen, dust, and ordinary PM2.5 in a closed bedroom, that is the right tool.

It is the wrong tool if you came here because of mold or a demand for 0.003-micron filtration. Paying Blueair prices and expecting IQAir particle claims is how this category disappoints people.

Coway Airmega 400S ($449–$549) sits next to Blueair if you care more about the app and an on-device AQI number than about the last step of particle size. It is a strong default for a first serious purifier. It is not a substitute for IQAir.

Closed bedroom, mold or ultrafine particles: IQAir HealthPro Plus.

Open living space, same particle concern: AirDoctor 5500.

Closed bedroom, allergies and dust, no ultrafine requirement: Blueair Classic 480i. Choose Coway Airmega 400S if you want the sensor and app more than Blueair's noise floor.

One unit cannot do both a large open plan and a sealed bedroom well. If the budget allows two, put the stricter filter where you sleep and the high-CADR unit where you cook.