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What air-purifier CADR do I need?

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People matching a portable purifier to room size. The decision this page isolates is narrow on purpose: estimate a cadr class from room area. Fit and capacity are the expensive mistakes. Settle those before you commit to a finish or a brand.

Estimate CADR class

CADR class

Large-room CADR

About 300 smoke-CADR planning floor

Compare options with at least:

  • 200 sq ft
  • Use the manufacturer’s CADR and recommended room size, not a health claim

Example products for What air-purifier CADR do I need?

Real products that fit this planning category. Specs come from the manufacturer’s product page. These are examples, not rankings.

Check Large-room CADR examples on Amazon

Compare the official examples

The table below is a side-by-side of the official examples on this page. Columns are published facts—maker, planning class, and notes taken from the official page—not scores. Coway Airmega 230, Levoit Core 400S, and Blueair Blue Pure 211i Max are included so you can see how classes differ, then open the official page for the current specification.

Published facts for the example products on this page. Not a ranking.
ExampleMakerPlanning classesPublished notes
Coway Airmega 230CowayMedium, Compact, LargeHEPA; Published CADR
Levoit Core 400SLevoitMedium, LargeSmart HEPA; Room-size rating
Blueair Blue Pure 211i MaxBlueairLarge, MediumHigh CADR; Washable prefilter

What to verify before you buy

How this estimate works

Use a 1.5 CADR-per-square-foot planning floor and raise it when pets or dust are present.

Know the limits

  • CADR is not a medical or allergy-treatment claim.
  • Filter replacement cost is separate.
  • Provider specifications and program terms can change and must be verified on official pages.

Frequently asked questions

How does the air purifier cadr work?

It converts room square feet into a planning class using a published rule. Use a 1.5 CADR-per-square-foot planning floor and raise it when pets or dust are present. The headline is a class such as Medium, Compact, and Large, not a vendor ranking.

Is Coway Airmega 230 better than Levoit Core 400S?

This page does not rank Coway Airmega 230, Levoit Core 400S, and Blueair Blue Pure 211i Max. Coway Airmega 230 and Levoit Core 400S are listed because they are real products with official pages that map to different or overlapping classes. The useful question is which class matches your inputs.

Do the product links earn Decision Lantern a commission?

Yes, when a product name or “View on Amazon” link goes to Amazon. Those are associate links. Decision Lantern may earn a commission at no extra cost to you. Official manufacturer pages are separate and are not tagged.

Sources

  1. AHAM air-cleaner certification, Association of Home Appliance Manufacturers. Retrieved .

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