Blueair · SP4i
Ready to buy
The retained reference is $449.99 current direct U.S. price. Optional wood or metal bases, pre-filter colors and subscriptions change checkout cost; confirm one-time purifier-only pricing. Confirm an exact genuine replacement filter is available before the return window closes.
Current market
Each line carries its own check date because price, software, specifications, and product cycle do not age at the same speed.
Optional wood or metal bases, pre-filter colors and subscriptions change checkout cost; confirm one-time purifier-only pricing. Confirm exact current U.S. checkout price, tax and delivery before paying.
Blue Signature Large is a defended high-CADR option when compact furniture form, quiet performance and app control matter, provided the buyer accepts always-on electrostatic assistance and verifies replacement-filter cost and privacy terms.
Other paths
These are not generic competitors. Each one represents a different way to buy into the same market.
Blueair
Coway
What changed
Older observations stay in the ledger when the current view changes. That lets a buyer tell the difference between an old complaint, an active issue, and a problem that was corrected.
Blue Signature Large was checked against exact manufacturer identity and operating material, current U.S. price, filter availability and cost, room-size test basis, independent comparison and bounded owner evidence.
Each amount stays tied to its source and capture date. Conflicting prices remain visible until the seller resolves them.
Current reference priceA structured timeline will begin with the next source capture
Owner experience
Owner discussion returns to side-outlet placement, app pairing, sensor response, odor expectations and tolerance for always-on electrostatic assistance rather than a universal air-quality outcome.
These are self-reported experiences from different room volumes, ceiling heights, layouts, sources, outdoor conditions, fan speeds, filter ages, placements, app versions, electrical conditions and individual sensitivities. They identify checks to run and do not prove exposure reduction, symptom improvement, gas removal, smoke safety, mold remediation, reliability or failure rates.Exact-model owners discuss sensor response, odor expectations, app pairing, side airflow, furniture use and filter reminders. Experiences remain self-selected.
Try the intended furniture placement without blocking airflow, review app permissions and compare operation and sound with a mechanical-only alternative.
1 evidence recordSources
The page separates what a source states directly from what we conclude across sources.
Blueair identifies exact model SP4i as a low table-like purifier with 455 cfm smoke CADR, app control, particle automation, OdorFence-treated carbon and integral electrostatic assistance.
$449.99 current direct U.S. price was retained for exact model SP4i. Optional wood or metal bases, pre-filter colors and subscriptions change checkout cost; confirm one-time purifier-only pricing
The exact SP4i ships with a washable fabric pre-filter and one Blue Signature Particle & Carbon filter using the OdorFence treatment; decorative bases and pre-filters do not change the core model AHAM figures are 455 cfm smoke, 434 dust and 450 pollen, with a 705-square-foot recommendation at 4.8 ACH under an eight-foot-ceiling standardized basis Blueair specifies 23 to 55 dB and 3.5 to 42 W; RTINGS measured 429 cfm PM1 CADR at maximum and 213 cfm at or below 45 dBA for its exact sample Particle sensing drives the display and auto mode. It does not replace a calibrated monitor for CO, CO2, formaldehyde or gases, and auto behavior can favor lower sound over a buyer's target air-change rate
The genuine Blue Signature replacement filter is $99.99 with maker guidance up to one year under RealTrack; pollutant load, fan use and subscription pricing change annual cost Vacuum or wash and fully dry the outer fabric, keep the side outlet and inlets open, replace rather than wash the main filter and reset through the display or app after replacement Remote control, schedules, history and alerts use Blueair's app, Wi-Fi, account and cloud service; core fan control remains on-device, while privacy, support lifetime and outage behavior require review Blueair offers a one-year warranty extendable to three years by registration, a 30-day direct trial, exact filter supply and app support; registration and seller terms should be retained
EPA treats portable filtration as a supplement to source control and clean-air ventilation, sizes particle cleaners by CADR and room volume, separates particle from gas filtration and states that no air cleaner removes every pollutant.
AHAM's suggested room size uses 4.8 air changes per hour and publishes separate tobacco-smoke, dust and pollen CADRs; room height and desired repetition remain part of sizing.
CARB certification addresses low ozone emissions and electrical safety under its regulation; CARB explicitly says listing does not establish cleaning effectiveness or complete health safety.
Independent 2026 testing measures PM1 CADR, low-noise delivery, sound, filter construction and the non-disableable electrostatic system on an exact sample.
Exact-model owners discuss sensor response, odor expectations, app pairing, side airflow, furniture use and filter reminders. Experiences remain self-selected.
Blue Pure 211i Max is the high-output connected cylinder value alternative at $349.99 current direct U.S. price.
Airmega 400 is the quiet dual-filter large-room mechanical platform alternative at $649 current direct U.S. price.
Manufacturer identity, exact filter and manual or support material, current U.S. price, AHAM or published CADR and room-size basis, independent comparative or instrumented editorial, CARB ozone context, EPA limitations and bounded owner evidence were checked on August 17, 2026. This desk covers complete current U.S.-market portable room air purifiers for serious home use. It excludes HVAC filters, industrial scrubbers, dehumidifiers, unsupported marketplace devices, filter-only products and cosmetic-only variants. CADR measures particle clean-air delivery under stated conditions; it is not a gas-removal rating, health guarantee or proof that one unit serves a whole home. Room-size headlines at one, two and 4.8 air changes per hour are not interchangeable. Sound, energy, filter efficiency, sensor readings, app features, auto modes, carbon labels, HEPA wording, CARB listing and ENERGY STAR status each have separate test boundaries. Source control and clean-air ventilation remain primary. No purifier prevents, treats or diagnoses illness, guarantees exposure reduction or smoke safety, remediates mold or assures universal indoor-air outcomes. Carbon monoxide alarms, moisture repair, professional hazardous-material work and public-health guidance remain separate needs.
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