Search for Blueair air purifier decibels and the answer is on almost every product page Blueair runs. Most pages go further than many brands do, naming both ends: so many dB "on low" and so many "on high fan speed". What the pages do not do is agree with themselves every time, and that changes which numbers you can lean on.
We read the US product page for every air purifier on Blueair's store, plus the user manuals and support articles Blueair links to. Twenty current models carry a noise figure. This page lists all of them, explains how Blueair labels its numbers, and ranks each model only against others whose figure describes the same thing.
Our picks are listed above, with full specifications for each.
Every Blueair spec table has a "Sound level" line. Most print a range such as "23-53 dB"; a few name the ends instead, as in "Low setting: 19 dB High setting: 46 dB". Below the spec table, most pages also answer "What are the noise levels?" with a sentence of the form "Operates quieter than a whisper on low at 23 db and is no louder than 53 dB on high fan speed." Where the FAQ and the spec table agree, the low figure is the low setting and the top figure is the high fan speed.
Three things are missing. No current product page states a measuring distance. Most print plain "dB", while the DustMagnet 5440i page prints "dB(A)". And "low" is never pinned to a named speed. Blueair's own guide to the Blue Pure Max speeds says "Night mode: lowest fan speed" and "Speed One: low fan speed", so a figure "on low" could describe either one. Night mode may be as quiet or quieter, but Blueair prints no separate figure for it.
On units, Blueair's own blog says "At Blueair, we use dB(A) values (decibel with A-weighted value) since we believe it to be the best rating for perceived sound level." That post dates from 2020, and the current pages mostly print plain dB. The one current manual that gives a figure, for the DustMagnet, footnotes it "Sound pressure according to GB/T18801", a Chinese air cleaner standard. Because the DustMagnet page prints dB(A) and the others do not, we keep it in a group of its own.
Low end labelled "low", in dB, quietest first
- Blue Pure 411i+ Max: 19 dB low, 46 dB high; 259 sq ft at 4.8 ACH.
- Blue Pure Mini Max Auto: 19 dB low, 44 dB high; 105 sq ft.
- Blue Signature Small: 19 dB low, 50 dB high; 248 sq ft.
- Blue Signature Medium: 19 dB low, 54 dB high; 498 sq ft.
- Blue Pure 511i Max: 19 dB low; the spec table says 19-48 db and the FAQ 42 dB on high; 237 sq ft.
- Blue Pure Mini Max (sold as the Blue Pure Mini Max Bundle, $139.99): spec table 19-44 dB, FAQ 19 dB low and 42 dB on high; 107 sq ft; three speeds and no air sensor.
- Blue Signature Mini: "Low setting: 20 dB High setting: 42 dB" in the spec table, "under 20db" on low in the FAQ; 127 sq ft; sold as a 2-pack.
- Blue Pure 511: the spec table says 24-49 dB, the FAQ 22 dB low and 44 dB high; 189 sq ft.
- Blue Pure 211i Max: 23 dB low, 53 dB high; 674 sq ft.
- Blue Pure 311i Max: 23 dB low, 50 dB high; 439 sq ft.
- Blue Signature Large: 23 dB low, 55 dB high; 705 sq ft.
- Blue Pure 311i+ Max: the spec table says 23-50 dB, the FAQ 25 dB low and 50 dB high; 525 sq ft.
- ComfortPure 3-in-1 T10i and T20i: 24 dB low, 52 dB high on both; 175 and 352 sq ft. These also heat and cool.
- Mini Restful Sunrise Clock Air Purifier: the FAQ and banner say 18 dB on low, but the spec table says 21 - 48 dB; 140 sq ft.
Range only, neither end labelled, in dB
- 2-in-1 Pro Purify + Humidify: 20 - 56 dB; 391 sq ft; no CADR on the page.
- Classic Pro CP7i: 24-55 dB; 609 sq ft. It was listed but sold out on blueair.com when we checked.
- 2-in-1 Purify + Humidify: 24-52 dB; 360 sq ft.
- PetAir Pro: 29 - 58 dB; 271 sq ft. It is a pet bed with a purifier built in.
Printed in dB(A)
- DustMagnet 5440i: 31 - 50 dB(A) on the page; the manual gives 30-50 dB for the 5410i, 5415i and 5440i, as sound pressure.
Blueair's US site has carried product pages for the DustMagnet 5210i, 5240i and 5410i, the Classic Pro CP9i, the Classic 405 and 605, and the Protect 7470i from the HealthProtect line, but those pages no longer load, so we leave them out.
Top of the range, by room size
A bigger purifier moves more air at full speed, so we rank top figures only within a size group, using Blueair's own room size at 4.8 air changes an hour, and only where the high end is labelled and the page agrees with itself.
For a small room, rated under 200 sq ft, the Blue Signature Mini is lowest at 42 dB, then the Mini Max Auto at 44 dB and the ComfortPure T10i at 52 dB. The Mini Max Bundle and the 511 have conflicting figures and sit outside this ranking.
For a bedroom-sized unit, rated from 200 to 350 sq ft, the 411i+ Max is lowest at 46 dB, then the Blue Signature Small at 50 dB. The 511i Max says 42 dB in its FAQ and 48 in its spec table, so we rank it on neither. Our bedroom air purifier guide sets the 411i+ Max beside other brands' units at the setting you sleep on.
For a large room, rated above 350 sq ft, the 311i Max and 311i+ Max tie at 50 dB, then the ComfortPure T20i at 52 dB, the 211i Max at 53 dB, the Blue Signature Medium at 54 dB and the Blue Signature Large at 55 dB. Our large-room air purifier guide sets the 211i Max and 311i Max beside other brands' bigger units.
What the gaps mean
Decibels are logarithmic. Roughly every 10 dB sounds about twice as loud, so the gap between 19 dB on low and 54 dB on high on the same Blue Signature Medium is huge: the top end sounds many times louder. A gap of 2 or 3 dB between two Blueair models is small, and with no distance stated it may be no gap at all. Our decibel chart sets published appliance figures beside everyday sounds such as a whisper and a fridge.
The low end also says nothing about how much air is moving. CADR is measured at a purifier's highest speed, so a model rated far above your room can sit on a low speed and still keep up, which is the quietest way to own any purifier.
Blueair's quiet features, by their real names
HEPASilent. Blueair's name for its filtration, which it says "combines electrostatic and mechanical filtration" so it works "faster and quieter than traditional HEPA". Its Quiet Mark article explains the idea: charging particles first "allows the use of a less dense filter, so more air can be pushed through with less noise and less energy." The footnotes differ by page. Most say "When similar CADR was measured, Blueair models with mechanical and electrostatic filtration achieved less noise with less energy than same models with only H13 HEPA mechanical filtration." The ComfortPure and 2-in-1 pages say "Noise refers to the dB(A) difference in acoustic power", and the 511 page says "Noise refers to acoustic power at max. fan compared to Blue Auto models." These are claims about the technology, not figures for a model, so we rank nothing on them.
Night mode. Blueair's support article says "the fan will run at the lowest fan speed and the LED lights will dim down." The Blue Pure Max guide adds that in Night mode "the LEDs on the air purifier are fully dimmed and the air purifier is at its quietest setting". The Blue Signature Small manual says the Night Mode button turns off all the lights and limits the fan to Fan Speed 1, "avoiding noise or light disruptions." The DustMagnet works differently: Blueair says its Night mode still follows the air sensor, but "the fan speed will only increase to the medium level to keep noise levels low." On the ComfortPure, Night mode "Turns the device to the lowest fan speed and lowest brightness", and heating is not available while it is on.
Noise shield. The Blue Pure Max models have a shield around the motor. Blueair says it ensures "powerful performance without compromising on noise" and asks owners not to throw it away when changing the filter.
Auto, Eco and Pet modes. Auto mode raises the fan as the particle sensor reads worse air, so a burst of cooking smoke can take any Blueair to the top of its range at night. Eco mode appears on the Classic Pro CP7i, both ComfortPure models and the Blue Signature Small. The ComfortPure manual says it "Sets device on standby after it detects clean air for over 10 minutes", and the Classic Pro page says ECO saves energy "until pollutants are detected." On the PetAir Pro, Pet mode "auto detects your pet & switches to the quietest mode & fan speed".
Quiet Mark. The Mini Restful page says it is "QuietMark certified". Blueair does not publish the figure behind the certification, so we rank nothing on it.
Keeping a Blueair quiet
The manuals give simple advice. Under "My air purifier is making too much noise", the Classic Pro manual says "Set a lower fan speed. The air purifier should be quieter." It also lists "The plastic sealing is still on the filter" as a cause, so take the plastic off a new filter. Keep the noise shield in place on a Blue Pure Max. Wash or vacuum the fabric pre-filter, because a clogged intake makes the fan work harder for the same air.
Six current pages give two figures. The Blue Pure 511 spec table says 24-49 dB while its FAQ says 22 dB on low and 44 dB on high. The 511i Max spec table says 19-48 db and its FAQ 42 dB on high. The 311i+ Max spec table says 23-50 dB and its FAQ 25 dB on low. The Mini Restful spec table says 21 - 48 dB, while its banner and FAQ say 18 dB. The Mini Max Bundle spec table says 19-44 dB and its FAQ 42 dB on high. The Blue Signature Mini spec table says 20 dB on the low setting and its FAQ "under 20db"; we rank it only on its high figure, which appears once. The DustMagnet 5440i page and manual also differ, by 1 dB at the low end, by unit, and on CADR and room size. We list every figure and give none of these an award on the lower one.
How Blueair compares
This page ranks Blueair models only against each other. For how they sit among other brands, on each maker's own published figures, see our guide to the quietest air purifiers. Since Blueair, like most makers, states no measuring distance, read our explainer on why decibel ratings rarely compare across brands before treating a gap of a decibel or two as real.
How we chose
We read Blueair's US air purifier collection and opened the product page for every model, plus the user manuals and support articles Blueair links to. We recorded each noise figure in Blueair's words, with the setting Blueair ties it to, and noted where a spec table and an FAQ on the same page disagree. We sorted the low figures into labelled and unlabelled groups, kept the one dB(A) figure apart, and ranked top figures only within a size group, using Blueair's room size at 4.8 air changes an hour. Prices are Blueair's US list prices on October 4, 2026.
We did not measure any of these purifiers. Every figure here is Blueair's own, from its product pages, manuals and support articles, and Blueair states no measuring distance on any current product page. Owners' rooms, floors and filters will change what they hear.
