๐ Household
Air Purifier Room Size Calculator
Air purifiers are rated by CADR, the cubic feet per minute of filtered air they deliver. The rule of thumb is a CADR of two-thirds of the floor area for an eight-foot ceiling, and higher for rooms with allergies or smoke.
How it works
Room length
Room width
Ceiling height
Air changes per hour
Room area
Room volume
CADR needed
CADR needed
Max room for a CADR 300 unit
Frequently asked questions
How do I use the Air Purifier Room Size Calculator?
Fill in the fields above โ the result recalculates instantly as you type. Everything runs in your browser, so the values you enter are never collected or stored.
Is this calculator free?
Yes. It is completely free, requires no account, and works on phones, tablets and desktops.