Head to head

Dyson Purifier Hot+Cool Formaldehyde HP09 vs Blueair Blue Pure 211+ Auto

Blueair Blue Pure 211+ Auto leads 4 to 1 on the 5 rankable specs and costs $460 less, which makes it the straightforward pick.

Catalog as of September 1, 2026

Why, in numbers

CADR: Dyson Purifier Hot+Cool Formaldehyde HP09 lists 190 CFM class (Air Multiplier 77 gallons/sec circulation) (Dyson sheet, 2026-09-02); Blueair Blue Pure 211+ Auto lists 353 CFM (Smoke), 347 CFM (Dust), 380 CFM (Pollen) (Blueair sheet, 2026-09-02).
Coverage area: Dyson Purifier Hot+Cool Formaldehyde HP09 lists 500 sq ft room size with 350° oscillation (Dyson sheet, 2026-09-02); Blueair Blue Pure 211+ Auto lists 550 sq ft (4.8 air changes/hr) / 1,320 sq ft (2 air changes/hr) (Blueair sheet, 2026-09-02).
Room size: Dyson Purifier Hot+Cool Formaldehyde HP09 lists Medium to large bedrooms, living rooms up to 500 sq ft (Dyson sheet, 2026-09-02); Blueair Blue Pure 211+ Auto lists Large living rooms, open floor plans, master suites (Blueair sheet, 2026-09-02).
Filter types: Dyson Purifier Hot+Cool Formaldehyde HP09 lists 360° Glass HEPA H13 + Activated Carbon + Cryptomic Formaldehyde filter (Dyson sheet, 2026-09-02); Blueair Blue Pure 211+ Auto lists Washable fabric pre-filter + HEPASilent main filter (Particle + Carbon) (Blueair sheet, 2026-09-02).
Filter life: Dyson Purifier Hot+Cool Formaldehyde HP09 lists 12 months (HEPA/Carbon) / Permanent Formaldehyde catalyst (Dyson sheet, 2026-09-02); Blueair Blue Pure 211+ Auto lists 6 months (Blueair sheet, 2026-09-02).

Manufacturer list price, not a live offer. Confirm current pricing before you buy.

Dyson Purifier Hot+Cool Formaldehyde HP09

$7991 spec win

Swap

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Blueair Blue Pure 211+ Auto

$3394 spec wins

Swap

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Buying for

Every rankable spec counts once. Pick a lens to score only what matters for your air purifier.

Straight answer

Overall: 1 to 4

Buy the Blueair Blue Pure 211+ Auto.

Leads 4 of 5 rankable overall specs; Dyson Purifier Hot+Cool Formaldehyde HP09 takes 1.
CADR: 353 CFM vs 190 CFM class
Coverage area: 550 sq ft vs 500 sq ft room size with 350° oscillation
It is also $460 cheaper.

Check first: the Blueair Blue Pure 211+ Auto has no Wi-Fi app. Tick them under deal-breakers if that rules it out.

1 Dyson Purifier Hot+Cool Formaldehyde HP095 rankable of 11 specsBlueair Blue Pure 211+ Auto 4

Deal-breakers

tick what would make you walk away

No Wi-Fi approw
No schedules or remote control from your phone.
Clear:Dyson Purifier Hot+Cool Formaldehyde HP09 · MyDyson App, voice control via Alexa, G…Trips:Blueair Blue Pure 211+ Auto · One-touch Auto Mode
Over 55 dB on highrow
Louder than normal conversation at full speed.
Trips:Dyson Purifier Hot+Cool Formaldehyde HP09 · 46 dB (Low) – 62 dB (Max)Trips:Blueair Blue Pure 211+ Auto · 23 dB (Low) – 56 dB (Turbo high)
Under 1,000 sq ft coveragerow
Undersized for an open-plan living area.
Trips:Dyson Purifier Hot+Cool Formaldehyde HP09 · 500 sq ft room size with 350° oscillati…Trips:Blueair Blue Pure 211+ Auto · 550 sq ft

At a glance

The handful of numbers that decide most purchases in this category.

2 of 2 differ

CADR

Dyson

190 CFM class (Air Multiplier 77 gallons/sec circulation)

Blueair

353 CFM (Smoke), 347 CFM (Dust), 380 CFM (Pollen)

Coverage area

Dyson

500 sq ft room size with 350° oscillation

Blueair

550 sq ft (4.8 air changes/hr) / 1,320 sq ft (2 air changes/hr)

True 3-Year Cost of Ownership (TCO)

Upfront price + 3 years of consumables, fees & essential add-ons

Dyson Purifier Hot+Cool Formaldehyde HP09

Upfront list price$799

3-Yr 360° Combi Glass HEPA + Carbon (Every 12 months (~$80/yr))+$240

3-Year Estimated Total$1,039

Blueair Blue Pure 211+ Auto

Upfront list price$339

3-Yr Foldable Particle+Carbon filter (Every 6 months (~$45/yr))+$135

3-Year Estimated Total$474

Room Placement & Bedroom Noise Check

Physical clearance required for airflow, wall placement, and bedroom noise levels.

Ergonomic & Spatial Check

Wall Clearance Required

Cylindrical 360° filters cannot sit flush against walls without choking intake.

Dyson

Cylindrical base: needs 12 in airflow clearance around unit

Blueair

Requires 12 in perimeter airflow space

Nighttime Sleep Mode Noise

Levels below 25 dB are virtually silent for light sleepers.

Dyson

28 dB night mode with dimmed LCD

Blueair

Standard sleep speed

Unit Footprint & Dimensions

Dyson

Bladeless oval loop (30.0 × 8.1 × 8.1 in; 12.6 lb; heats & cools)

Blueair

Standard room purifier footprint

The 90-Day Owner Regret Check

Documented ergonomic quirks, hardware annoyances, and maintenance realities reported by real owners.

Post-Purchase Truths

Dyson: What to watch for

Hidden Cost
High replacement filter cost (~$80 each).
The catalytic formaldehyde combo filter is significantly more expensive than standard box purifiers from Levoit or Coway.

Blueair: What to watch for

Maintenance
Requires periodic filter replacements to maintain airflow and odor capture.
Activated carbon and HEPA media gradually saturate, needing replacement once or twice yearly depending on air pollution and pet shedding.

Dyson Purifier Hot+Cool Formaldehyde HP09$7991 win

Blueair Blue Pure 211+ Auto$3394 wins

Performance Filters Usability & Smart Design & Ownership

11 of 11 attributes differ. Identical rows are dimmed.

Performance

leads 2-0

Performance specifications. Middle column is Dyson Purifier Hot+Cool Formaldehyde HP09, right column is Blueair Blue Pure 211+ Auto.
CADR	190 CFM class (Air Multiplier 77 gallons/sec circulation)	353 CFM (Smoke), 347 CFM (Dust), 380 CFM (Pollen) (wins this row: higher)
Room size	Medium to large bedrooms, living rooms up to 500 sq ft	Large living rooms, open floor plans, master suites
Coverage area	500 sq ft room size with 350° oscillation	550 sq ft (4.8 air changes/hr) / 1,320 sq ft (2 air changes/hr) (wins this row: higher)

Filters

leads 1-0

Filters specifications. Middle column is Dyson Purifier Hot+Cool Formaldehyde HP09, right column is Blueair Blue Pure 211+ Auto.
Filter types	360° Glass HEPA H13 + Activated Carbon + Cryptomic Formaldehyde filter	Washable fabric pre-filter + HEPASilent main filter (Particle + Carbon)
Filter life	12 months (HEPA/Carbon) / Permanent Formaldehyde catalyst (wins this row: higher)	6 months

Usability & Smart

leads 1-0

Usability & Smart specifications. Middle column is Dyson Purifier Hot+Cool Formaldehyde HP09, right column is Blueair Blue Pure 211+ Auto.
Noise levels	46 dB (Low) – 62 dB (Max)	23 dB (Low) – 56 dB (Turbo high) (wins this row: lower)
Energy consumption	40 W (Purifier mode) / 1,575 W (Heating mode)	38 W max power consumption
Smart features	MyDyson App, voice control via Alexa, Google Assistant, Siri Shortcuts	One-touch Auto Mode (no Wi-Fi app)
Air quality sensors	Solid-state formaldehyde sensor, PM2.5, PM10, VOC, NO2, Temperature, Humidity	Integrated particle sensor with 3-color air quality LED indicator

Design & Ownership

leads 1-0

Design & Ownership specifications. Middle column is Dyson Purifier Hot+Cool Formaldehyde HP09, right column is Blueair Blue Pure 211+ Auto.
Weight	12.6 lb (5.7 kg)	12.5 lb (5.7 kg) (wins this row: lower)
Warranty	2 years	2 years (with product registration)

Most rows are from the official spec sheet. Marked rows are other published figures or our summary, not lab tests we ran.

Dyson Purifier Hot+Cool Formaldehyde HP09 source Blueair Blue Pure 211+ Auto source

Which one should you buy

Pick this one if

Dyson Purifier Hot+Cool Formaldehyde HP09

3-in-1 purifier, ceramic space heater, and cooling fan with solid-state catalytic formaldehyde sensor.

Combines HEPA H13 purification, fast ceramic heating, and cooling fan in one
Destroys formaldehyde continuously without filter replacement
Fully sealed whole-machine HEPA H13 standard prevents bypass

What you give up

CADR airflow is lower than dedicated box purifiers
Expensive upfront purchase price

Full Dyson Purifier Hot+Cool Formaldehyde HP09 specs →

Pick this one if

Blueair Blue Pure 211+ Auto

High-capacity large-room air purifier with 360-degree HEPASilent filtration and machine-washable fabric pre-filters.

High 353 CFM CADR cleans a 550 sq ft living room in just 12.5 minutes
HEPASilent electrostatic + mechanical filtration maximizes airflow and efficiency
Interchangeable washable fabric pre-filters in multiple designer colors

What you give up

No mobile app or Wi-Fi schedule controls (one-button operation)
Reaches 56 dB at highest turbo fan setting

Full Blueair Blue Pure 211+ Auto specs →

Best for each use

Bedrooms

Quiet nights: low-speed noise, sleep mode, schedules from your phone

For bedrooms, buy the Blueair Blue Pure 211+ Auto.

Leads 2 of 2 rankable bedrooms specs.
Noise levels: 23 dB vs 46 dB
Weight: 12.5 lb vs 12.6 lb
It is also $460 cheaper.

Big rooms & allergies

Open-plan rooms or allergies: CADR, coverage, filter grade

For big rooms & allergies, buy the Blueair Blue Pure 211+ Auto.

Leads 2 of 3 rankable big rooms & allergies specs; Dyson Purifier Hot+Cool Formaldehyde HP09 takes 1.
CADR: 353 CFM vs 190 CFM class
Coverage area: 550 sq ft vs 500 sq ft room size with 350° oscillation
It is also $460 cheaper.

Low running cost

Cheap to own: filter life, power draw, warranty

Too close to call on low running cost from the spec sheets. Only filter life is rankable here.

Energy consumption: 40 W vs 38 W max power consumption
Warranty: 2 years vs 2 years

Every answer above is scored from published figures. A lens uses only the rows that matter for that use, including marked rows that are not on the official sheet. Switch lenses interactively in the panel above.

Done deciding?

Open the full standalone spec sheet for either device.

Dyson Purifier Hot+Cool Formaldehyde HP09 spec sheet Blueair Blue Pure 211+ Auto spec sheet

Manufacturer pages: Dyson Purifier Hot+Cool Formaldehyde HP09 ↗ · Blueair Blue Pure 211+ Auto ↗

Common questions

Which is cheaper, the Dyson Purifier Hot+Cool Formaldehyde HP09 or the Blueair Blue Pure 211+ Auto?

Blueair Blue Pure 211+ Auto costs $460 less at list price.

What is the biggest catch with the Dyson Purifier Hot+Cool Formaldehyde HP09 or Blueair Blue Pure 211+ Auto?

Blueair Blue Pure 211+ Auto has this deal-breaker: no Wi-Fi app. No schedules or remote control from your phone.

Which is better for bedrooms, the Dyson Purifier Hot+Cool Formaldehyde HP09 or the Blueair Blue Pure 211+ Auto?

For bedrooms, buy the Blueair Blue Pure 211+ Auto. Leads 2 of 2 rankable bedrooms specs. Noise levels: 23 dB vs 46 dB

What cannot be compared from spec sheets?

Of the 11 specs tracked here, 6 are descriptive and cannot be ranked on numbers alone. Spec sheets also cannot measure subjective factors like build quality, real-world performance, or comfort.

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