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Our pick if it has to go on the wall

Rabbit Air MinusA2

US MinusA2

$599.95US price, checked Oct 13, 2026

Slim wall-mount purifier for rooms near 280 ft², with $95 yearly filters

Check price at Rabbit Air Full review →

Our pick for a small bedroom or office

Blueair Blue Pure 511

US model, store item 109994, with one Particle + Carbon filter and an Arctic Trail pre-filter

$99.99US price, checked Oct 13, 2026

Low-cost purifier for one room up to about 190 ft², with filters at $48 a year

Check price at Blueair Full review →

Criterion	Rabbit Air MinusA2	Blueair Blue Pure 511
US price	$599.95Checked Oct 13, 2026 · Price details in the review	$99.99Checked Oct 13, 2026 · Price details in the review
Three-year ownership estimate	$884.95 Incomplete known subtotal. Not included: energy use.	$243.93 Incomplete known subtotal. Not included: energy use.
Choose if	You want a purifier on the wall, not the floor, in a bedroom or office up to about 280 ft².	A bedroom or office up to about 190 ft² where you want a cheap, simple purifier with low filter costs.
Main trade-off	$599.95 buys a smoke CADR of 180, and Rabbit Air doesn't say who tested that figure.	It covers only one small room, and it has three manual speeds with no air sensor or auto mode.
Key specifications	CADR (smoke, dust, pollen): 180, 193 and 200; Rabbit Air doesn't name the test standard Room size: Rabbit Air says 408 ft² at 4 air changes an hour or 815 ft² at 2 (8 ft ceiling, top speed). Those match its 218 CFM airflow. On the 180 smoke CADR, 4.8 air changes an hour fits about 280 ft². Noise: 25.6 to 51.3 dBA across five speeds; no per-speed breakdown Power draw: 6 to 61 W (120 V, 0.85 A max); no per-speed or standby figures Filters: Washable pre-filter, medium, BioGS HEPA, one customized filter and activated carbon, plus an ion generator you can switch off Filter life and price: $95 kit (medium, HEPA, customized and carbon) every 12 months at 24/7, or up to 2 years at 12 hours a day; $14.95 spare pre-filter Size and weight: 20 × 21.4 × 7 in; 19.4 lb; wall-mount kit included Controls: Auto mode with particle and odor sensors, pollen mode and a light sensor; remote on the SPA-780A, Wi-Fi app control and no remote on the $619.95 SPA-780N	CADR (smoke, dust, pollen): 122, 123 and 123 cfm Room size: 189 ft² at 4.8 air changes an hour (one change every 12.5 minutes) Noise: 24 to 49 dB in the spec table; 22 dB on low and 44 dB on high in the FAQ Power draw: 16 W, a single figure with no low or high Filters: One Particle + Carbon filter behind a washable pre-filter Filter life and price: About 6 months; $23.99 per filter, $6.99 per pre-filter Controls: Three manual fan speeds and a filter-change light; no air sensor Size and weight: 13.4 × 7.9 × 7.9 in; 4.2 lb
Exact variant	US MinusA2	US model, store item 109994, with one Particle + Carbon filter and an Arctic Trail pre-filter
Dimensions	20 × 21.4 × 7 in (height × width × depth). Another spec section on the same page gives the height as 20.25 in. It weighs 19.4 lb, and the power cord is 9.33 ft.	13.4 × 7.9 × 7.9 in (height × width × depth). It weighs 4.2 lb.
Installation	None needed to stand it on the floor. It plugs into a 120 V outlet. A wall-mount kit comes in the box, and the manual says to drive the hanger screws into studs. On a wall it needs 2 ft of space below the ceiling and 8 in on each side. On the floor it needs 2 ft clear at the air outlet and 8 in at the intakes on each side.	None. Plug it in and it blows clean air out the top. Blueair's page links no manual, so it doesn't say how much wall clearance it needs.
Materials	Six stages: a washable pre-filter, a medium filter, a BioGS HEPA filter, one customized filter, an activated carbon filter and a negative ion generator. You pick the customized filter: Germ Defense, Toxin Absorber, Pet Allergy or Odor Remover. Rabbit Air says the HEPA media is treated to keep bacteria and mold from growing on the filter itself. The ion generator can be switched off.	A single Particle + Carbon filter sits behind a washable pre-filter. Blueair says the filter captures PM2.5, pollen, dust mite allergen and pet dander allergen. The carbon is aimed at light household odors such as smoke and cooking. Blueair calls the system HEPASilent, a mix of electrostatic and mechanical filtration. Pre-filters come in Arctic Trail, Night Waves and Winter Reed.
Warranty	Rabbit Air covers defects in materials and workmanship for 5 years from the original retail purchase. Its registration page says registering gets you the 5-year warranty and free round-trip shipping to its service center in the contiguous US. The manual asks you to register within 90 days of purchase. Filters, filter frames and cases, wall-mount brackets and cosmetic damage aren't covered. Rabbit Air may ask for proof of purchase.	One year from purchase, or two if you register. Blueair's warranty page gives 60 days to register, in your Blueair account or the app. That page doesn't name the 511, so the two-year term comes from the product page. You need to replace filters on Blueair's schedule and keep proof of purchase. Coverage is for the original owner only, and warranties aren't available through third-party resellers. In the first year a defective unit is exchanged for a new or equivalent one. During the registered extension, the replacement is refurbished. Coverage ends if the unit leaves the continental US or Canada. Filters are covered for 30 days.
Returns	90 days from purchase, with a prepaid return label, for orders bought on RabbitAir.com and shipped in the contiguous 48 states. It has to come back like new, in the original packaging with the remote and manual. Items that aren't like new may carry a restocking fee. Replacement filters can't be returned once unwrapped.	30 days from purchase for items bought directly from Blueair, sent back with Blueair's prepaid label. Filters and pre-filters that are used or out of their plastic wrap can't be returned. Shipping charges, including the $5 flat rate, aren't refunded. Blueair takes 10 to 14 days to process a return. The refund then reaches your original payment method within 3 to 5 business days.
Unresolved questions	Whether AHAM has verified its CADR figures Whether CARB certified it; the readable part of CARB's list held only recent entries Which test standard and lab produced the CADR figures Power draw and noise at each of the five speeds, and standby power Average power on auto, so the yearly electricity cost What warranty cover applies if you don't register	Whether it's listed in AHAM's Verifide directory or Energy Star's product finder; neither directory could be read Whether CARB has certified it; the part of CARB's list that loaded showed four other Blueair models Power draw on low, and which speed the 16 W figure refers to Noise at speed 2 Whether the electrostatic part of HEPASilent gives off any ozone Wall clearance and other setup guidance from the manual

These comparisons use published specifications, not head-to-head tests. Prices and terms are dated. Unknown costs are not zero. Check the exact variant before you buy.