Buying an Air Purifier? Just Do This One Thing

Forget the complex specs. To choose an effective air purifier, you only need to master one number: CADR (Clean Air Delivery Rate). Here’s the no-nonsense guide.

1. The One Rule: CADR Must Match Your Room

CADR measures how fast it cleans (in CFM). The rule is:

Your purifier’s Smoke CADR should be at least 2/3 of your room’s area (sq ft).

Minimum CADR = Room Length (ft) × Room Width (ft) × 0.67

2. Quick-Size Chart

Your Room Size (sq ft) Look for This CADR (CFM)
150 (small bedroom) 100+
300 (master bedroom/living room) 200+
450 (large living room) 300+
600 (extra large room) 400+

Tip: For high ceilings, allergies, or pets, choose a CADR 1.5x the calculated minimum.

3. Trust the Number (Wherever It’s From)

The CADR value is reliable if it comes from a major certification. You don’t need all three; any one is credible:

  • AHAM Verified: Directly certifies the CADR number.
  • ENERGY STAR: To certify efficiency, they rigorously test and publish the CADR.
  • DOE Compliant: Uses the same test method to set baseline rules.

Just find the CADR in the product specs—it’s trustworthy if the product has any of these labels.

4. Your 3-Step Shopping List

  1. Measure your room. Calculate: Length × Width.
  2. Find your CADR. Multiply your room’s area by 0.67. That’s your target.
  3. Match & Buy. Choose a model with a Smoke CADR at or above your target. Verify the number in the specs or on the ENERGY STAR/AHAM website.

Bottom Line: Don’t overthink it. Measure your room, find your target CADR, and pick a certified model that meets it. You’ll get clean air without the confusion.

Ready to experience cleaner air? Click HERE to visit the CleanForce special offers page.

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