CADR Calculator

Enter your room dimensions to calculate the minimum Clean Air Delivery Rate (CADR) your air purifier needs for effective cleaning.

Minimum CADR Required
240
CFM (Smoke CADR)
Room: 180 sq ft · Volume: 1,440 cu ft

Recommended Air Purifiers

Based on 240 CFM minimum CADR, here are purifiers that meet or exceed your room's requirements:

How CADR Is Calculated

Formula: Minimum CADR = (Room Sq Ft × Ceiling Height × ACH) ÷ 60

The result is in CFM (cubic feet per minute), which is the unit used for Smoke CADR ratings. AHAM recommends a CADR that delivers at least 4.8 air changes per hour in your room. For allergy and asthma sufferers, aim for 6-8 ACH.

Read the full CADR and ACH guide →