Calculators & Tools

Calculators and interactive tools for the numbers that matter: room-size to CADR, air changes per hour, running cost, and true filter cost.

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Interactive

Air Purifier Finder: Find Your Match in 2 Minutes

Answer four quick questions and get an air purifier matched to your room size, your air, and your budget — plus the top alternatives. Free, no email.

Interactive

Air Purifier Room Size Calculator: What CADR Do You Need?

Enter your room size and get the exact CADR to look for, using the AHAM rule. Includes a wildfire-smoke setting. Free air purifier sizing calculator.

Interactive

Air Changes Per Hour Calculator: Is Your Purifier Strong Enough?

Enter your room size and a purifier's CADR to see how many air changes per hour it delivers — and whether that's enough for allergies and asthma. Free tool.

Interactive

Air Purifier Filter Cost Calculator: The Real Price of Ownership

A cheap air purifier with pricey filters can cost more than an expensive one. Work out the true multi-year cost of any purifier with this free calculator.

Interactive

Air Purifier Running Cost Calculator: What It Costs to Run

Work out what running an air purifier costs per day, month, and year using its wattage, your hours, and your local electricity rate. Free calculator.