CADR Calculator: Clean Air Delivery Rate in CFM & m³/h

Here we have two types of calculators to calculate the required CADR from air purifiers for your room:

CADR Calculator using universal formula (dynamic and versatile)
Tobacco Smoke CADR Calculator using AHAM’s Formula (limited usage)

CADR Calcualtor (universal formula):

You can easily calculate the required CADR (universal formula) using:

Room area (square footage or L x W),
Ceiling height, and
Your preferred air exchange rate (ACH) per hour.

Calculate the required CADR from the calculator below:

Formula:

1. CADR in CFM = (ACH x Room Area x Ceiling Height) / 60

2. CADR in m3h = CADR in CFM x 1.699

What is CADR?

CADR or Clean Air Delivery Rate represents an air purifier’s filtering efficiency. It Indicates the air purifier’s filtration rate at a specific time. CADR is expressed in CFM (cubic feet per minute) or m³/h (cubic meter per hour).

For example, an air purifier with a labeled CADR 200 CFM means, it delivers 200 cubic feet of filtered air every minute on its highest fan speed settings.

The term ‘Clean’ means ‘filtered air,’ and it doesn’t guarantee filtration quality. CADR is more likely a quantitative measure than a qualitative standard.

Filtration quality depends on filter types, grades, and other factors. For example, a True HEPA-grade filter can filter out 99.97% of 0.3 micron-sized particles.

How Important is the CADR?

The CADR rating is the key metric for evaluating an air purifier based on efficiency. Also, you have to consider the other aspects such as filter types, filter surface area, effective air intake-outlet design, etc.

In a nutshell,

Air Purifier Efficiency = CADR ratings
Air Purifier Effectiveness = Filter types

Tobacco Smoke CADR Calculator:

You can easily calculate the required Tobacco Smoke CADR (AHAM’s Formula) using:

Your Room area (square footage or L x W).

*Ceiling height is always constant at 8 feet.

Formula:

Tobacco Smoke CADR = Room Area / 1.55

AHAM’s CADRs Certificate Sample:

AHAM’s CADR

AHAM (Association of Home Appliance Manufacturers) certifies air purifiers with three different CADR ratings: Tobacco Smoke, Dust, and Pollen. Tobacco smoke CADR represents the efficiency against ultrafine particles, Dust CADR for fine particles, and the Pollen CADR is for coarse particles.

Here, you can find the list of AHAM-certified air purifiers with room size recommendations.