CADR Rating: What Is It?

CADR Rating: What Is It?

You can’t compare air purifiers without their respective CADR ratings divulged. This rating system is one of the most reliable means of identifying the performance of an air purifier. Read on and learn more about it. 

When buying an air purifier, many people often encounter the term “CADR” or Clean Air Delivery Rate. In a nutshell, the CADR for air purifiers is a system designed to assess the capability of various air purifiers designed for residential purposes. Its measurement includes the removal of pollen, dust, and smoke.

Technically speaking, the Clean Air Delivery Rating can help an individual assess the overall performance of an air purifier. It can also be used when comparing one air purifier to another.

Air Purifier CADR (Clean Air Delivery Rate) Meaning

An air purifier with a human on its background
An air purifier with a human on its background

Image Source: iStockphoto

In the past, people assessed air purifiers based on their filters and maximum airflow, which is measured via cubic feet per minute (CFM).

The Association of Home Appliances Manufacturers (AHAM) designed a universal metric that air purifier companies should use to measure the overall effectiveness of their products. It gave birth to the Clean Air Delivery Rate (CADR) test. The CADR meaning in air purifiers remains a vital information for consumers.

Benefits of CADR: Why Is It Important?

An air purifier inside a workspace
An air purifier inside a workspace

Image Source: iStockphoto

The benefits that CADR rating provides:

  • The CADR of air purifiers tells people how powerful and efficient an air purifier is. The numbers don’t lie, so they help buyers decide which air purifier can meet their requirements for indoor air purification.
  • The CADR system also elaborates on the ability of an air purifier to remove specific pollutants. Specifically, there are three common contaminants that are being measured in this system: tobacco smoke, dust, and pollen. Each of these pollutants has designated CADR particle numbers. The higher the number, the faster the air purifier can clean the said contaminants.
  • It is easier to buy an AHAM-verified air purifier than those that are not because of the CADR rating. Air purifiers that aren’t certified by AHAM don’t have this particular information. Therefore, their actual capabilities are ambiguous.


An air purifier inside a living room
An air purifier inside a living room

Image Source: iStockphoto

Is Higher CADR The Better?

A good CADR rating reflects the strength of the airflow of the air purifier. When the air cleaner excels in this particular aspect, you can expect that your room will always be free from foreign contaminants. It is not coincidental that air purifiers with powerful airflow also have high CADR ratings.

There’s an advantage in picking air purifiers that score well in the CADR test. And if you have the capacity to purchase these air purifiers right from the get-go, you should buy them right away.

A high AHAM CADR rating indicates that an air purifier can absorb more contaminants in the air.

What Is the Best Air Purifier CADR?

When it comes to the best CADR rating, you should aim for the highest possible scores. For specific contaminants, the best CADR rating for air purifier is as follows:

  • Smoke CADR – 450
  • CADR rating dust – 400
  • CADR rating pollen – 450

What CADR Rating Do I Need

The best CADR rating follows the “2/3 Rule.” Specifically, the CADR of the air purifier you choose should be equal or at least two-thirds of the area of your room.

Let’s take an example. Suppose you have a room that has a size of 150 square feet. Here, you need an air purifier that has a CADR rating of at least 100 for dust, pollen, and smoke. If you are dealing with wild smoke, AHAM suggests that the CADR rating for smoke should be equal to or bigger than the size of your room.

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

We often see people pair “CADR CFM” into the same equation.

We can put “CFM CADR” into a better perspective. For example, if an air purifier has a 300 CFM and 100 percent efficiency, its CADR would be 300. If an air purifier has a 300 CFM, but with a 75 percent efficiency, its CADR would be 225.

CADR Units

The CADR air purifier meaning lies in the fact that AHAM tests the ability of air purifiers through its filters. Specifically, there are three aspects being measured here, and that’s the performance of an air purifier in dealing with specific contaminants, such as smoke, pollen, and dust.

Smoke represents the smallest particle, while dust is the biggest one. CADR pollen tends to be in the middle ground. Air purifiers with a high smoke CADR rating notably excel in removing microscopic airborne contaminants.

CADR Calculator

You can calculate CADR based on your own. You can do this by using the following factors below:

  • Room size or the actual square footage of the area where you want to place the air purifier (length x width)
  • Height of the room’s ceiling
  • Your desired air exchange rate per hour (ACH) is expressed in the number of air cycles an air purifier can do per hour.

These are two formulas that you can use here. They are as follows:

  • CADR in CFM – (ACH x Area of the room x Height of the ceiling) / 60
  • CADR in m3h – CADR in CFM x 1.699

By the way, the minimum required CADR is as follows:

  • CADR in CFM – 140 CFM
  • CADR in cubic meters per hour – 238 m3/h

CADR Rated 100

Based on the recommendations of AHAM, you need to take the CADR rating of an air purifier and multiply it by 1.55. This will give you an idea of the ideal coverage of an air purifier. By the way, this calculation is made on the basis that the ceiling height of the room is 8 feet or less.

For example, a 100 CADR air purifier will be able to purify rooms of 155 square feet. Oppositely, you can also divide the square footage of your room by 1.55 to get the ideal CADR purifier for you.

CADR Rated 125

If you want to know the actual room size that an air purifier can clean, you have to take its CADR rating and multiply it by 1.55. Hence, a CADR rated 125 air purifier can clean rooms up to 193 square feet. That’s a good CADR rating.

CADR Rated 300

A HEPA CADR 300 air purifier would be able to clean rooms of up to 465 square feet.

Divide the square footage of your room by 1.55 so that you will get the ideal CADR rating for an air purifier. Air purifiers with CADR 300 cubic feet per minute are great for medium- to large spaces.

How Does CADR Rating Guide for Air Purifiers Help? (CADR Scale Chart Explained)

As mentioned earlier, there’s no such thing as right or wrong when it comes to CADR rating. Air purifiers are built differently. Some of them are designed for small rooms, while others are for medium- and large-size floor spaces. Of course, there’s an appropriate CADR rating for each of these settings.  The chart below could help you out.

CADR scales Micron Types Fittable Room sizes
CADR Rated 100 Pollen, dust, and smoke Up to 100 square feet
CADR Rated 125 Pollen, dust, and smoke Up to 200 square feet
HEPA CADR 300 Pollen, dust, smoke, and microscopic pathogens Up to 465 square feet

CADR Rating for Smoke

The maximum CADR rating for smoke is 450. The higher the number, the more particles in the smoke can be captured. Essentially, the smoke CADR rating is based on the ability to capture particles that are as small as 0.09 microns.

CADR Rating for Pollen

In the Clean Air Delivery Rate scale, pollen has a maximum CADR score  of 450, which is similar to smoke. Air filters should be able to capture 5 to 11-micron particles to ensure that they can trap pollen and prevent them from spreading allergies.

CADR Rating for Dust

In the CADR rating chart, the highest score for dust is 400. Air purifiers that have a high dust CADR rating can remove pollutants that range from 0.5 to 3 microns. AHAM certified CADR air purifiers tend to excel in removing dust in the air.

CADR Air Purifier Ranking on the Market

The AHAM utilized a systematic approach for creating the CADR test. Hence, all AHAM-verified air purifiers are tested through a standardized approach.

Hence, it is always possible to rank different air purifier models and brands through this metric. Their air filter CADR rating will help you find the best air cleaner for your home, office, or building.

Below are some of the top-rated air purifiers in the market with their CADR air filter ratings. However, some of these air purifiers didn’t disclose their CADR ratings.

Product Name CADR Smoke CADR Dust CADR Pollen
Levoit Core 200s Air Purifier 118 118 118
Molekule Air Mini  –  –
iQAir Perfect 16 Air Purifier  –  –  –
Coway Storm Air Purifier  –  –  –
Dyson DP04 Air Purifier  –  –   –
GermGuardian AC4825 Air Purifier 99 118 125
Honeywell HPA 300 Air Purifier 300 320 300
BlueAir 211 Air Purifier 350 350 350
Shark Air Purifier 4  –  –  –
Winix C535 Air Purifier 232 243 246
Rabbit A3 Air Purifier 257 262 315

Levoit Air Purifier CADR Rating

Levoit Core 200s
Levoit Core 200s

Image Source: Canva

Here, we have the Levoit Core 200s, a reputable air purifier for rooms with small square footage. You can also check out the Levoit Core 300, which is a “bigger version” of the 200s. The Levoit Core 300 CADR rating is notably higher than the Core 200, so that’s something that you should take into account. Meanwhile, most Levoit CADR ratings aren’t available for old models.

Molekule CADR Rating

Molekule Mini
Molekule Mini

Image Source: Molekule

The next stop is the Molekule brand, represented by the Molekule Mini Air Purifier. Unfortunately, Molekule doesn’t submit its air purifiers to AHAM tests. Hence, there is no real way of knowing its AHAM ratings for air purifiers.

iQAir CADR Rating

iQAir Air Purifier
iQAir Air Purifier

Image Source: iQAir

The Perfect 16 of iQAir is one of its best-selling air purifiers. It isn’t available on online retailers, though. You have to buy it directly on its website. Similar to Molekule, iQAir doesn’t submit its air purifiers for AHAM testing. Therefore, its air purifier Clean Air Delivery Rate is something we can only guess now.

Coway CADR Rating

Coway Storm
Coway Storm

Image Source: Coway

The Coway is a reliable source of residential air purifiers. Its Coway Storm Air Purifier has been designed to provide optimal air circulation for the best air cleaning results. It’s also packed with multiple features, but its CADR rating isn’t available due to non-submission.

Dyson CADR Rating

Dyson DP04 
Dyson DP04 

Image Source: Dyson

Dyson is a popular brand of home cleaners, such as vacuums. However, it also has a fair share of high-quality residential air purifiers. Interestingly, the Dyson air purifier CADR scores aren’t disclosed. We can’t assess its actual performance. Even the Dyson TP04 CADR rating and the Dyson Pure Cool CADR rating aren’t available.

GermGuardian CADR Rating

GermGuardian AC4825
GermGuardian AC4825

Image Source: GermGuardian

The GermGuardian AC4825 is a type of tower air purifier. It is one of the best air purifiers of GermGuardian, as it is equipped with essential filtration mediums. Specifically, the GermGuardian CADR rating is suitable for small spaces, with scores of 99 (smoke), 188 (dust), and 125 (pollen).

Honeywell CADR Rating

Honeywell HPA300
Honeywell HPA300

Image Source: Honeywell

Honeywell is one of the top manufacturers of air purifiers today. Its air cleaners are impeccably powerful, as indicated by the Honeywell HPA300 CADR rating. However, it is not only the HPA300 that you should check out from this brand. Multiple Honeywell air purifier CADR ratings show that the brand’s air cleaning systems are worth checking.

Curious about where are honeywell air purifers made, Click here.

BlueAir CADR Rating

BlueAir 211+
BlueAir 211+

Image Source: BlueAir

Blueair is a trusted brand of air purifiers and air filters. It has manufactured numerous air cleaners suitable for small to large floor spaces. Moreover, Blueair CADR ratings are disclosed; hence, they are AHAM-tested. For instance, the Blueair 211 CADR rating is as follows: 350 (smoke), 350 (pollen), and 350 (dust).

Shark Air Purifier 4 CADR Rating

Shark Air Purifier 4
Shark Air Purifier 4

Image Source: Shark

Notably, the Shark Air Purifier 4 CADR Rating isn’t available. It indicates that the brand doesn’t submit its air purifiers for AHAM testing. However, many still trust this particular air purifier. It is hefty with features, such as a proprietary HEPA filter and automated technology. But since this air purifier’s CADR filter rating isn’t available, there’s no way of knowing its actual performance.

Winix C535 CADR Rating

Winix C535
Winix C535

Image Source: Winix

The C535 air purifier highlights the pinnacle of Winix’s air cleaning technology. It is ideal for spaces up to 360 square feet. It also contains the PlasmaWave technology for virus and bacteria neutralization. The Winix C535 CADR rating also proves its optimal air purification performance. This unit and Winix C545 CADR ratings are almost the same.

Rabbit Air CADR Rating

Rabbit A3
Rabbit A3

Image Source: Rabbit

The quality of the Rabbit A3 Air Purifier is something worth noting. It has a proprietary BioGS HEPA filter that excels in trapping microscopic contaminants. Even if the Rabbit Air CADR rating isn’t available, we can assume that the A3 is capable of removing various airborne threats in your rooms. By the way, this air purifier is for big rooms.

Air Purifiers With Best CADR Rating

There are a plethora of air purifiers that aced the CADR test. But if you want the best ones right from the get-go, then you should get the following air purifiers that we have listed here.

These air purifiers are manufactured by HisoAir. The latter is a reputable manufacturer of medical-grade, filter-based air purifiers for commercial and residential applications. See their provisions now.

Coverage CADR Rating
HisoAir HA-1968 air purifer for 2000 square feet 1500 m3/h
HisoAir HA-1601 air purifier  for 1,000 square feet 800 m3/h
HisoAir HA-1300 air purifer for 1,500 square feet 1500 m3/h


Understanding the CADR rating system is essential. It helps you navigate the vast sea of air purifiers in the market today. Through this rating system, you will be able to find which air purifier is suitable for your current air purification needs.

If you want the best air purifiers right from the get-go, get those air cleaners manufactured by HisoAir. Our company dedicates itself to the creation of high-quality air cleaners that are capable of comprehensive indoor air purification. Visit our website and see all our offers!

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