Air Quality Monitors – Comparison List 2020 Q4

It has been a while since the last time I updated the list with all the air quality monitors in the market. Just to be clear, there are a lot more Chinese knockouts that I haven’t included because they don’t have any support from the companies either they offer something unique.

This time the list includes some Pro-level indoor AQMs like the elichens
Indoor Air Quality PRO Station
and the NEMo XT – Indoor.

  • Prices may vary during time.
  • Some Companies don’t specify on their data sheet if their devices are capable to measure PM2.5 or PM10 and they just mention the word dust.
  • Some other companies say: Our product goes beyond CO₂ by analyzing substances that directly affect your well-being by measuring VOCs. They aren’t clear if their devices have CO₂ sensor.
  • Some of the devices are AQI Monitors and Air Purifiers Combo. On this list you can only read the features as an AQI monitor.

23 thoughts on “Air Quality Monitors – Comparison List 2020 Q4

    • I would suggest choosing the one that completes your ecosystem, HomeKit goes with Laser Egg and Google goes with Awair. It is a hard choice and this is the reason I tell you to look at these features (if they are important to you).


  1. Sotirios, thank you for updating the list. This was actually the way I discovered your website and I think it is the most comprehensive comparison out there. Very appreciated!
    Is there any way we can open / download it? It could be interesting to be able to sort it for various columns/rows.


  2. Great article, and glad to see our product (NEMo XT) makes the list!
    It might be a good idea, however, to separate general public-targeted and professional products, as there are significant differences in terms of sensors performances as well as prices between the two ranges?
    In addition, thanks to the modularity of our device, it is totally possible to measure CO by integrating an additional sensor.
    Other features that are important to smart buildings could maybe also be included: for example, thanks to a few sensors installed in some rooms, our unique data managing algorithm allows to simulate, then predict air quality for the coming hours in all the rooms of the building with an air quality index.

    Liked by 1 person

    • Hi, thank you for your kind comment.
      Footbot doesn’t have an actual CO2 sensor. It uses an algorithm to calculate the equivalent eCO2.

      The first generation Awair had an inaccurate PM sensor, the newer versions are better as they use a light scattering one which are far better than the LED optical sensors.

      Liked by 1 person

  3. How accurate then is the Foobot CO2? I’ve had a Foobot next to an IQAir in our bedroom for a bit and there appear to be significant discrepancies. I’ve not really taken time to analyze the data yet though. I may move the foobot up to where my TACX is setup since that gets huge CO2 swings when I ride and may be a better indicator.

    2 Questions:

    – How to balance between PM2.5 and CO2? Normally we like to open windows as often as possible and especially at night. A typical night w/ closed windows results in CO2 of 700-900 while open windows stays below 450 and definitely results in a better night’s sleep. However, when outside air has PM2.5 of 50 or 70 or 100 (thanks to the wildfires in California 2000 miles to our west) it is probably better to endure the higher CO2. What are the balance points? What levels of PM2.5 are less healthy than what levels of CO2?

    – My uRAD A3 is indicating consistent Formaldehyde of 7 ppm (all day every day) in our gym. It never varies. Similar for ozone that is consistently 20ppm all day every day. Normal? I’m wondering if I should move it outside for a bit to see what it gets out there.

    Thanks for all of the great info and knowledge!

    Liked by 1 person

  4. Foobot & Airboxlabs appears to suffer from three critical problems and should IMO be avoided.

    1) Foobot is extremely light sensitive. In a dimly lit room or one with florescent lighting it appears somewhat accurate. In a normally moderately lit room (incandescent/halogen/LED/sunlight) it indicates readings for PMx of 2x-5x all other monitors and much higher readings of VOC’s than a uRAD A3. In a brightly lit room or one with much sunlight, even if the sunlight is not directly on or near the foobot, it gives wildly inaccurate readings, on the order of 10x to 500x other monitors. This does not seem to happen with florescent lighting so it appears to be spectrum sensitive.

    2) eCO2 calculations can be off by a factor of 5. For example, when all other monitors are indicating 400-500 the Foobot indicates 2,000 or higher. I assume that this is correlated to the inaccurate PM & VOC measurements but it does not appear to be a direct correlation.

    3) Company Integrity. Foobot / Airboxlabs refused to give us a refund even though their monitor is clearly providing grossly inaccurate readings. They have a strict 30-day refund policy and unless the purchaser has other monitors to compare against the purchaser has no way of knowing if the Foobot is accurate or not within that 30-day period.

    Foobot / Airboxlabs has not replied to any of my concerns about inaccurate PMx and VOC measurements. They have replied only to the inaccurate CO2 measurements and simply said that CO2 is a non-issue so implying that we should simply ignore CO2 measurements anyway.

    Given their reaction to my emails they appear to be aware that they provide grossly inaccurate readings for CO2, PMx and VOCs and are not concerned about that.

    Following is my email conversation w/ Foobot / Airboxlabs:


    We purchased a Foobot about a year ago. We’ve been trying to use it to have fresher air in our home. Frequently the readings, particularly for CO2, have seemed extreme but we figured we just had high CO2 problems.

    We recently purchased an IQAir and have noticed extreme differences in CO2 and PM2.5 readings between the two, even in the same room. More recently we were able to compare these to 2 other IQAir’s and a Urad A3. The 3 IQAir’s and A3 were all within about 20% of each other on CO2 and PM2.5 while our Foobot was off by about 1500%.

    Our Foobot is currently indicating CO2 of 2000+, VOC’s of 845 and PM2.5 of -. While the IQAir sitting directly next to it shows CO2 of 518 and PM2.5 of 7.3

    If I open a window both will indicate lower CO2 of <450 after a bit. When the window is closed they will both rise but the Foobot will be over 2000 within a few minutes while the IQAir will slowly rise and never get above about 550 if nobody is in the room and maybe top out at 800 if someone is sitting at the table where both are located.

    I did try cleaning w/ compressed air but that didn't seem to make any difference.


    Thanks for reaching out to us with your concerns.  Foobot does not have a CO2 sensor. its an estimate based on voc levels hence "co2-eq" meaning equivalent. C02 is a non issue in homes and merely indicates human presence. the concentrations required for it to be harmful are exceeding unlikely. per ashrae, its not a good indicator of indoor air quality:

    "Note however that CO2 concentration is not a good indicator of the concentration and occupant acceptance of other indoor contaminants, such as volatile organic compounds off-gassing from furnishings and building materials. Thus CO2 concentration is not a reliable indicator of overall building air quality." 

    Click to access TC-04.03-FAQ-35.pdf


    So what you’re saying is that Foobot is inaccurate but that’s OK because CO2 doesn’t matter anyway? Why even calculate equivalent CO2 if it will be inaccurate and doesn’t matter?


    We included a rough estimate of CO2 as customers requested it over time.. its not a good metric of air quality and we never advertised being a CO2 monitor. pm 2.5 and VOC will affect your breathing health long before CO2 will.

    hope that clarification helps, Have a great day,. We are here if you have any additional questions or concerns.


    My emails asking about the inaccurate PMx and VOC measurements have gone unanswered.


  5. Note that we have noticed a quite serious problem w/ uRAD A3’s not performing temperature compensation with CO2 measurements which, if true, is critical flaw and calls in to question the accuracy of all uRAD products as this is a very basic element of CO2 measurement that should not have been missed.

    I posted something about it on the uRAD support discussion 10 days ago but have not received a response which is also concerning.


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