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Technology Guide

CADR Explained: How to Size an Air Purifier for Particles

Clean Air Delivery Rate helps compare particle-cleaning capacity. Learn how to use CADR with room area and ceiling height.

Updated September 2026•Research-based editorial

The core concept

Clean Air Delivery Rate is a useful particle-cleaning metric. EPA’s consumer guide gives example minimum CADRs of 65 cfm for 100 sq. ft., 130 for 200, 195 for 300, 260 for 400, 325 for 500 and 390 for 600, based on 8-foot ceilings.

Technology is only half the equation

A purifier also needs enough airflow for the room. For particle cleaning, standardized metrics such as CADR are easier to compare than broad marketing language. For gases, evaluate the dedicated gas-removal stage because particle metrics do not measure gas performance.

How this relates to Molekule

Molekule’s current Air Pro and Air Mini+ combine HEPA particle filtration, carbon and proprietary PECO technology. That hybrid design is why Molekule should be compared on both conventional purifier criteria and the evidence behind its additional treatment claims.

Practical buyer checklist

  • Identify the pollutant you actually want to reduce.
  • Measure the room and account for ceiling height.
  • Compare airflow/particle metrics where available.
  • Review noise, filters, energy and sensor features.
  • Verify current manufacturer specifications before purchase.
Research basis: Product specifications and current lineup details were checked against Molekule’s official product/help materials. General air-cleaner guidance follows the U.S. EPA Guide to Air Cleaners in the Home. Where independent-review observations are mentioned, they are attributed in the text. Airwise Atlas does not claim hands-on testing unless explicitly stated.