What Is CADR Rate?

Wondering what the CADR rate is and how air purifiers’ performance is rated? We got you!

How can a manufacturer, or a seller, provide standardized information about an air purifier’s effectiveness?

As always happens, there is a standard rate to measure air purifiers’ performances, and that is the CADR rate.

What Is CADR Rate
What Is CADR Rate

Key Takeaways

  • CADR is used to measure the performance and effectiveness of home air purifiers.
  • Only AHAM can rate air purifiers, so when you buy one, check that the rating comes from the AHAM.
  • Avoid comparing a US CADR rating with a Chinese one.
  • To measure the removing-particles effectiveness of a device, three types of particles are tested, and they are smoke, dust, and pollen. 

CADR Rate: Simplified!

The Clean Air Delivery Rate, shortened in CADR, is a metric that was designed and introduced to measure the performance and effectiveness of home air purifiers.

So, what does it measure?

The CADR score reflects the volume of air (measured in CFM, cubic feet/meter) cleaned from particles (of a determined dimension).

To measure the removing-particles effectiveness of a device, three types of particles are tested and they are smoke, dust, and pollen. They represent small, medium, and large particles; so, each of them is measured and assigned its own CADR score. 1

Read: Dust Allergies: Symptoms & Treatment With Air Purifier

Also Read: What Are AOC Carbon Filters?

What is CADR Certification?

The CADR certification program is possible because there is an association that has the responsibility of assigning the score.

If it wasn’t like that, anyone could put a score on the air purifier even though it doesn’t match the actual effectiveness of the device.

The association that oversees the CADR rating program is the AHAM, Association of Home Appliance Manufacturers.

Only AHAM can rate air purifiers, so when you buy one, check that the rating comes from the AHAM.

Why Is CADR Important?


Other than letting you know about the air purifier’s performance before you purchase it, the CADR rating provides the important advantage of providing the consumer with a way to compare air purifiers.

Of course, you need to know what the CADR score means, and we’re just about to provide this information.   

You can interpret the score like this:

·   if the CADR is 150, it means that the air purifier has 200 CFM per 75% efficiency;

·   if the CADR is 200, it means that the air purifier has 200 CFM but 100% efficiency.

Does CADR Have Anything To Do With The Efficiency Of The Filters?

Yes, the CADR can actually help you balance the two pieces of information.

For example, if an air purifier has a very high-efficiency filter, but low airflow, the CADR provides balanced information about the two data.

CADR Standards

The CADR rating has been used since 2016. China, however, uses another rating system, which can be considered a Chinese version of CADR.

Why should you know this? Because many air purifier manufacturers are Chinese, if you purchase a Chinese air purifier, you should be aware of the difference.

CADR Rating Scale

CADR Rating Scale

The CADR rate is different for different size of pollens and particles. For smoke and pollen, the CADR scale is from 0-450, for dust it is 0-400. This is the CDR rating scale for different types of particles:

  • Smoke CADR – 0-400 (Particles size from 0.9 and 1.0 μm)
  • Pollen CADR Scale: 0-450 (Particles size from 5 and 11 μm)
  • Dust CADR Scale: 0-450 (Particles size from 0.5 and 3 μm) 2

How Is CADR Calculated?

To calculate CADR, the air purifier is put in a room of size 1,008 cubic feet and is now started for 25 minutes to measure the level of contaminants against the pre-tested levels. The test results then show the CADR rating of dust, smoke particles, and pollen.

Is There Any Additional Information To Check?

Th eCADR provides enough information to give you an idea about the device’s efficiency. If you want to go for further details, you could check how the tests have been performed.

Also Read: AHAM: What It Is And What It Does?


The CADR is highly helpful, especially when you need to compare two different air purifiers.

However, always check the manufacturer, and avoid comparing a US CADR rating with a Chinese one.


What is the ideal CADR value?

An air purifier with the value of 80 CADR is considered good.

How to know what CADR value is suitable for my house?

To find the right CADR value you simply need to divide your room size size in square foot by 1.55.

How long should I run my air purifier?

You should run your air purifier 24×7.

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  1. https://www.bobvila.com/articles/cadr-rating/[]
  2. https://air-purifier-ratings.org/learn/cadr-ratings-scale/#:~:text=The%20CADR%20scale%20goes%20up,coverage%20of%20the%20air%20purifier.[]

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