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  • 6 VIDEOS
Aranet4 HOME air quality monitorARANET USA
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SAF Aranet4 Home: Wireless Indoor Air Quality Monitor for Office or School (CO2, Temperature, Humidity and More) Portable, Battery Powered, E-Ink Screen, App for Configuration & Data History

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Product details

Color White
Brand SAF
Product Dimensions 2.76"W x 2.76"H
Item Weight 104 Grams
Battery Description Alkaline

About this item

  • BREATHE EASILY: Aranet4 CO2 meter measures CO2 levels, temperature, relative humidity, and atmospheric pressure in real-time, empowering you to make informed decisions for healthy ventilation. No wonder it's the top-rated indoor air quality monitor in Amazon's CO2 monitor segment!
  • CABLE-FREE: The power-efficient e-ink display guarantees an extended battery life of up to 4 years for this wireless air quality monitor, ensuring worry-free monitoring without the hassle of cables and cords.
  • EASY-TO-USE: The color coding, prominent CO2 number on the display, and optional buzzer of this air quality meter alert you when the CO2 concentration becomes too high.
  • FREE & INTERACTIVE APP: A smartphone application for viewing and analyzing up to 90 days of historical data from your indoor air quality meter, complete with user-friendly graphs.
  • PREMIUM QUALITY: Aranet4 carbon dioxide detectors use nondispersive infrared sensor (NDIR) technology for the most precise and reliable CO2 measurements. Made in the European Union.
  • ENJOY THE HEALTH BENEFITS: Air quality monitor indoor use helps people take better care of the atmosphere around them, leading to improved focus, mood, and overall well-being.
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This item: SAF Aranet4 Home: Wireless Indoor Air Quality Monitor for Office or School (CO2, Temperature, Humidity and More) Portable, Battery Powered, E-Ink Screen, App for Configuration & Data History
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Product details

  • Language ‏ : ‎ Spanish, English
  • Product Dimensions ‏ : ‎ 0.94 x 2.76 x 2.76 inches; 3.67 ounces
  • Item model number ‏ : ‎ TDSPC003.001
  • Batteries ‏ : ‎ 2 AA batteries required. (included)
  • Date First Available ‏ : ‎ July 18, 2019
  • Manufacturer ‏ : ‎ SAF Tehnika
  • ASIN ‏ : ‎ B07YY7BH2W

Product Description

Improve your well-being!

The video showcases the product in use.The video guides you through product setup.The video compares multiple products.The video shows the product being unpacked.

What we breathe makes a big difference in how we feel. This is why air quality monitors have become so amazingly popular. The Aranet4 is a specialized sensor providing a wealth of health-centric data to you so you can make informed decisions about ventilation and where to spend your time.

Take care of your air!

CO2, CO2 monitor, carbon dioxideCO2, CO2 monitor, carbon dioxide

Carbon Dioxide

This odorless gas is harmless in small quantities. However, increased concentrations negatively impact productivity, health, and indoor air quality.

HumidityHumidity

Temperature

Humans operate best under specific conditions. Studies show that maintaining a range of 68-76 °F (21-22 °C) is ideal within homes, offices, etc.

TemperatureTemperature

Relative Humidity

Finding the correct balance of moisture (30-60%) in an indoor environment is key to ensuring human comfort.

PressurePressure

Atmospheric Pressure

Atmospheric pressure affects human well-being, impacting breathing, blood pressure, and ear pressure, especially during altitude changes.

Air quality, ari quality monitor, air quality monitoring, co2, co2 monitoringAir quality, ari quality monitor, air quality monitoring, co2, co2 monitoring

Free app

  • It allows you to see the measurement history going back 90 days or see CO2 measurement in real-time.
  • Allows you to see the readings you had during the night or while you were away from home.
  • Makes it easy to track progress, when implementing changes in your home ventilation, so you can find the best solutions for your home and make smarter decisions.
  • Makes it easy to change various settings for your Aranet device.
  • You can turn on the buzzer and change the warning thresholds to custom settings.

  • High CO2 levels can negatively affect your well-being, comfort, and productivity. For example, if CO2 levels reach 1000 ppm, your cognitive abilities drop by 15%. At 1400 ppm and above, they decrease by a staggering 50%.

  • Because it provides a higher precision than regular electrochemical sensors because CO2 is uniquely detectable with no interference from other gasses. Besides that the lifespan of the NDIR sensor is much longer and less recalibration is needed.

  • Aranet4 excels with multi-sensor accuracy, real-time alerts, app connectivity, and user-friendly design, highly praised by numerous satisfied customers.

Wireless and portable – take your Aranet4 wherever you go!

Indoor air qualityIndoor air quality

Aranet4 HOME is easy and fun to use. You can move it between rooms in your house, take it to hotels during business trips, or monitor the air quality in classrooms, conference rooms, museums, parties, concerts, and so many other places. Bring Aranet4 HOME with you wherever you go!

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Customer reviews

4.7 out of 5 stars
1,538 global ratings

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Customers say

Customers find the humidity meter useful for measuring air quality and helping to improve indoor air quality. They find it easy to use, set up, and maintain. The sensor is accurate and consistent, and the factory calibration was already perfect. The meter is portable enough to take around and check various areas for CO2 levels.

AI-generated from the text of customer reviews

134 customers mention "Functionality"104 positive30 negative

Customers appreciate the humidity meter's functionality. They find it works well and provides consistent temperature readings. The app functions smoothly and provides useful data. The e-ink screen is also appreciated. Overall, customers are satisfied with the product's performance and value for money.

"...For travel, or just in general, it's a great device to have...." Read more

"...monitor -- the product of Latvian engineering -- is one of the most awesome gadgets I have ever purchased...." Read more

"The aranet4 is such an excellent monitor, and really is the best bang for your buck in an accurate and easy to use monitor...." Read more

"...And I can see why--it's a fantastic piece of equipment. What I Love: --It's incredibly easy to set up, and easy to use...." Read more

125 customers mention "Air quality"104 positive21 negative

Customers appreciate the air quality meter. It measures CO2 levels accurately, and they find it useful for monitoring indoor air quality and understanding how different activities affect it. The meter helps improve air quality in homes and bedrooms by reminding them when to adjust air conditioning and ventilation. It keeps a record of the air quality data, providing accurate temperature and humidity readings. Many customers find the meter helpful for improving air conditioning and ventilation in their homes and restaurants.

"...It's just an incredible sensor to have -- you can pocket it or bring it somewhere in a backpack and still have CO2 measurements, where most sensors..." Read more

"...It's super interesting to analyze CO2 levels as you move into different spaces, e.g. when you board a plane, when the plain is airborne, etc.,..." Read more

"...The app is simple and does the job. It keeps a record of the air quality data, so I’ve started geeking out on comparing the air quality in different..." Read more

"...It measures temperature, CO2, air pressure and relative humidity. You can set the interval, too...." Read more

71 customers mention "Ease of use"67 positive4 negative

Customers find the humidity meter easy to use and set up. They appreciate the nice user interface and the quality apps that extend the device's usability. The meter is easy to maintain and monitor CO2 levels. It provides valuable data and is the simplest way to tell if the air around you is safe or dodgy.

"...this monitor in the main living area of our house and it's every easy to monitor when the C02 is accumulating and we need to crack a window or turn..." Read more

"...The color coding on the device makes it super easy to understand when the air quality is getting bad, and the buzzer is a neat feature too, although..." Read more

"...What I Love: --It's incredibly easy to set up, and easy to use. --The battery life has been great...." Read more

"...It is easy to use. If you download their app to your phone, you can easily download the data it collects...." Read more

68 customers mention "Accuracy"61 positive7 negative

Customers appreciate the humidity meter's accuracy. They find it easy to use and calibrate, with good factory calibration. The CO2 readings are consistent, though some devices vary greatly on air quality measurements. Overall, the meter provides useful information for monitoring air quality and CO2 levels.

"...Other details are worth mentioning beyond the sensor accuracy and app integration, though. E-ink, as a display type, is just awesome...." Read more

"...It's extremely accurate, unlike other cheap CO2 monitors on Amazon...." Read more

"...an excellent monitor, and really is the best bang for your buck in an accurate and easy to use monitor...." Read more

"This thing is synonymous with accuracy. It's pricey. But definitely well made. Solid...." Read more

54 customers mention "Portable"54 positive0 negative

Customers appreciate the humidity meter's portability. They find it lightweight, compact, and easy to carry around. The meter is great for keeping in a room and getting feedback about COVID risk and ventilation. It's small, easy to use, and read, with fantastic battery life.

"...just an incredible sensor to have -- you can pocket it or bring it somewhere in a backpack and still have CO2 measurements, where most sensors can't..." Read more

"...The batteries last for many months. It's very compact -- easily fits in a pocket...." Read more

"...easy to set up, the battery life is excellent, and it's easy to bring with you anywhere. The app works well and is likewise a quick and easy setup...." Read more

"...I love that the Aranet4 is portable. I've taken it with me on trips, and it's kind of become my travel buddy...." Read more

49 customers mention "Build quality"36 positive13 negative

Customers appreciate the humidity meter's build quality. They find it reliable, with an intuitive app UI and high-quality monitor. The device is highly portable and easy to read, making it an impressive and useful tool for improving physical and mental well-being.

"...Totally worth the money and a reliable, trustworthy device for monitoring a really important aspect of our health." Read more

"...--The battery life has been great. --So far, it has survived a plane trip and constant use for several months...." Read more

"...It's pricey. But definitely well made. Solid. The e-paper display is crystal clear, and ensures the battery lasts a VERY long time...." Read more

"...packaging clearly retaped, amazon return barcode on packaging, manual ripped, and tool missing...." Read more

48 customers mention "Battery life"44 positive4 negative

Customers appreciate the humidity meter's battery life. They find it lightweight, portable, and accurate. The display barely uses any battery power, and it stores data for a 14-day period. The batteries only need replacing about once every two years. It takes standard AA batteries and has an E-ink display that draws less energy.

"...Also, there's no backlight, which is why the battery life is good, but keep this in mind too, if you want to see it in the dark...." Read more

"...The e-paper display is incredibly clear. The batteries last for many months. It's very compact -- easily fits in a pocket...." Read more

"...It's easy to set up, the battery life is excellent, and it's easy to bring with you anywhere...." Read more

"...The e-ink display is clear, and the battery just keeps going - haven’t had to charge it yet!..." Read more

52 customers mention "Bluetooth connectivity"27 positive25 negative

Customers have different experiences with the humidity meter's Bluetooth connectivity. Some say it connects easily to their phones and pairs with them, allowing them to track readings and see graphs. Others mention using WiFi at point of use and that the app frequently loses connection.

"...Other details are worth mentioning beyond the sensor accuracy and app integration, though. E-ink, as a display type, is just awesome...." Read more

"...for a little over a year and then, all of a sudden stopped communicating with the app...." Read more

"...It syncs with your phone using Bluetooth, so you can see CO2 levels over time (this is a killer feature that other monitors don't have)...." Read more

"...The most glaring flaw is that it does not have WIFI...." Read more

Nice heads up to have
5 out of 5 stars
Nice heads up to have
Nice to know (or even as a reminder when you walk by) when I should open my windows or turn on our vents. Easy to see how over night the number goes up with lots of people breathing in the house (and dogs). Then in the morning using vents or opening windows it drops back to a good level.Would be great in places with fires or big cities for sure, still useful in the burbs though.
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Top reviews from the United States

  • Reviewed in the United States on April 14, 2022
    I've owned several CO2 sensors. In particular, I've had 2 Awair Glow units, 1 first-generation Awair unit, 1 second-generation Awair unit, and a TIM10 CO2 sensor. Of these sensors, the TIM10 is my "gold standard" sensor, but it has the very, very annoying property of requiring AC power. Aranet4 promised to be a battery-powered CO2 sensor that could output data to an app. It delivers, but it requires calibration out-of-the-box, in my opinion.

    Measured against known good sensors (particularly my TIM10), my Aranet4 sensor read about 75ppm higher than the environmental level out-of-the-box. The app warns you that performing calibration will permanently erase the factory calibration data, which is somewhat scary, but I did it anyway. In order to validate that the calibration was successful, I had my trusted TIM10 sensor outdoors, connected to AC power, out of the sun, with the Aranet4 directly next to it, on a substantially windy day with extremely good air quality (as measured by PM2.5 and PM10 presence from AirNow and Purple Air). The floor, outdoors, in this configuration, as read by the TIM10 unit, was 380ppm of CO2. Before calibration, in the same environment, Aranet4 reported 480ppm. After calibration, Aranet4 reported within 15ppm of TIM10, which I considered a success, particularly given the rarity of having such a low reading. All of the Awair units bottom out at 400ppm.

    Following calibration, for the last few weeks, I've kept an eye on Aranet4 and TIM10 when they've been in the same room. There's approximately a 10-15ppm disagreement between TIM10 and Aranet4, which I consider a very acceptable deviation given that Aranet4 is battery powered, and TIM10 is AC powered.

    On the app side, Aranet4 provides a serviceable iOS app. The iOS app itself is perfunctory. It provides graphing, exporting data (as csv, including CO2, pressure, humidity, temperature, and date of sample), and basic reporting features. It doesn't support dark mode, though, as an example of its perfunctory nature. The app developers didn't consider the performance impacts that storing all of the data would have on the graphing component, though, so the app gets laggier the more data the sensor measures. You're also only going to get a week of data for historical measurement.

    Other details are worth mentioning beyond the sensor accuracy and app integration, though. E-ink, as a display type, is just awesome. It looks very nice, aesthetically. Each refresh blanks the screen temporarily, though. Keep this in mind, if you decrease the measurement interval (you can measure as frequently as once per minute). Also, there's no backlight, which is why the battery life is good, but keep this in mind too, if you want to see it in the dark.

    I've taken this sensor on an airplane, and it works great there too. It's just an incredible sensor to have -- you can pocket it or bring it somewhere in a backpack and still have CO2 measurements, where most sensors can't go. For travel, or just in general, it's a great device to have. After calibration, it measures very accurately, and I'm happy with my purchase all around. However, I'd say calibration is mandatory.

    I've included a screenshot of a graph made from the CSV, as well as the CSV data from the unit itself.
    Customer image
    5.0 out of 5 stars
    After manual calibration, this is a very awesome battery-powered CO2 sensor

    Reviewed in the United States on April 14, 2022
    I've owned several CO2 sensors. In particular, I've had 2 Awair Glow units, 1 first-generation Awair unit, 1 second-generation Awair unit, and a TIM10 CO2 sensor. Of these sensors, the TIM10 is my "gold standard" sensor, but it has the very, very annoying property of requiring AC power. Aranet4 promised to be a battery-powered CO2 sensor that could output data to an app. It delivers, but it requires calibration out-of-the-box, in my opinion.

    Measured against known good sensors (particularly my TIM10), my Aranet4 sensor read about 75ppm higher than the environmental level out-of-the-box. The app warns you that performing calibration will permanently erase the factory calibration data, which is somewhat scary, but I did it anyway. In order to validate that the calibration was successful, I had my trusted TIM10 sensor outdoors, connected to AC power, out of the sun, with the Aranet4 directly next to it, on a substantially windy day with extremely good air quality (as measured by PM2.5 and PM10 presence from AirNow and Purple Air). The floor, outdoors, in this configuration, as read by the TIM10 unit, was 380ppm of CO2. Before calibration, in the same environment, Aranet4 reported 480ppm. After calibration, Aranet4 reported within 15ppm of TIM10, which I considered a success, particularly given the rarity of having such a low reading. All of the Awair units bottom out at 400ppm.

    Following calibration, for the last few weeks, I've kept an eye on Aranet4 and TIM10 when they've been in the same room. There's approximately a 10-15ppm disagreement between TIM10 and Aranet4, which I consider a very acceptable deviation given that Aranet4 is battery powered, and TIM10 is AC powered.

    On the app side, Aranet4 provides a serviceable iOS app. The iOS app itself is perfunctory. It provides graphing, exporting data (as csv, including CO2, pressure, humidity, temperature, and date of sample), and basic reporting features. It doesn't support dark mode, though, as an example of its perfunctory nature. The app developers didn't consider the performance impacts that storing all of the data would have on the graphing component, though, so the app gets laggier the more data the sensor measures. You're also only going to get a week of data for historical measurement.

    Other details are worth mentioning beyond the sensor accuracy and app integration, though. E-ink, as a display type, is just awesome. It looks very nice, aesthetically. Each refresh blanks the screen temporarily, though. Keep this in mind, if you decrease the measurement interval (you can measure as frequently as once per minute). Also, there's no backlight, which is why the battery life is good, but keep this in mind too, if you want to see it in the dark.

    I've taken this sensor on an airplane, and it works great there too. It's just an incredible sensor to have -- you can pocket it or bring it somewhere in a backpack and still have CO2 measurements, where most sensors can't go. For travel, or just in general, it's a great device to have. After calibration, it measures very accurately, and I'm happy with my purchase all around. However, I'd say calibration is mandatory.

    I've included a screenshot of a graph made from the CSV, as well as the CSV data from the unit itself.
    Images in this review
    Customer imageCustomer imageCustomer imageCustomer image
    181 people found this helpful
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  • Reviewed in the United States on March 7, 2023
    This CO2 monitor -- the product of Latvian engineering -- is one of the most awesome gadgets I have ever purchased. It's extremely accurate, unlike other cheap CO2 monitors on Amazon. It syncs with your phone using Bluetooth, so you can see CO2 levels over time (this is a killer feature that other monitors don't have). The e-paper display is incredibly clear. The batteries last for many months. It's very compact -- easily fits in a pocket.

    It's super interesting to analyze CO2 levels as you move into different spaces, e.g. when you board a plane, when the plain is airborne, etc., since CO2 concentration is a proxy for COVID risk. I was on an old Embraer jet, probably 30 years old, and the CO2 levels hit the highest level I have ever seen, 3550ppm! (The outdoor level is about 450ppm.)

    Also, not many people know this but you can measure cognitive decline starting at about 900ppm of CO2 -- and many apartments, especially new constructions, get way over this level. See the paper "Associations of Cognitive Function Scores with Carbon Dioxide, Ventilation, and Volatile Organic Compound Exposures in Office Workers: A Controlled Exposure Study of Green and Conventional Office Environments", Allen et al., Environmental Health Perspectives, for some shocking numbers about this.

    Once you start frequently monitoring CO2 levels, closing the biofeedback loop, two things happen: (1) you develop a new 6th sense -- you can start to predict the exact CO2 level just by how the air feels when you breathe it in. I can often guess the CO2 level to within 50ppm, without looking at the Aranet4. Weird and pretty cool. (2) You start to get really conscious just how stuffy the air is, and how much your cognitive function slows, even when the CO2 levels are high.
    133 people found this helpful
    Report
  • Reviewed in the United States on December 30, 2023
    The aranet4 is such an excellent monitor, and really is the best bang for your buck in an accurate and easy to use monitor. We have used this in all the rooms of our home to measure air flow and how quickly C02 builds up - especially useful in the kitchen during various cooking processes and in the bedrooms overnight - but we have also brought it to work to measure the C02 and get an idea of the air flow in various offices as well. It's easy to set up, the battery life is excellent, and it's easy to bring with you anywhere. The app works well and is likewise a quick and easy setup. We keep this monitor in the main living area of our house and it's every easy to monitor when the C02 is accumulating and we need to crack a window or turn on an exhaust fan. It's been illuminating. This item is also very accurate, and more so than others and cheaper version. Totally worth the money and a reliable, trustworthy device for monitoring a really important aspect of our health.
    29 people found this helpful
    Report

Top reviews from other countries

  • John Danaway Lai
    4.0 out of 5 stars Attractive CO2 temperature and humidity monitor. However, app needs some improvement.
    Reviewed in Singapore on May 25, 2024
    Living in a closed space with generally poor ventilation in an apartment, is the reason why I purchase this product. However , after been using it for over 2 weeks now, I have come into conclusion that most of us may not even need it because the CO2 in a closed space in my apartment rarely goes above 800ppm throughout the day. The only situation where it can go above 800ppm is when gas stove is used. However, carbon dioxide monitor or reader can be useful if you live in a rather tight space whereby there are three or more occupants as CO2 is mainly produced by respiration or breathing other than from burning gas. As you can see in the picture here, the screen on the aranet 4 is quite a bit sharper and contrasty than the inkbird and the design is more attractive due to semi transparent plastic case and the underlying board design is partially visible whereas inkbird has a bit of off-white coloration. The measurement is very similar to one another due to similar NDIR sensor used. As mentioned, the main deciding factor whether you need this or not is how many occupants in a space or how crowded the space is. More people occupying same space at same time, the higher the CO2 produced. For the app, I like how you can just drag along the chart to see the reading. However, aranet app only allows 7 days of data to be kept on the device before it gets overwritten where as the inkbird can keep data on the device for up to 30 days. Basically, aranet app is more polished , however, data storage is only limited to 7 days when set to 5 minutes measurement interval instead of 30 days (on device) to 1 year on inkbird (only when is synced to the phone).
    Addendum : Aranet has released a firmware in Dec 2023 that allows you set how long the data can be stored on the device and this depends the measurement interval, i.e. 2 minutes interval equivalent to 7 days of storage; 5 minutes for 15 days ; and 10 minutes for 30 days of storage .
    Besides CO2 readings, you will also get ambient temperature, humidity and atmospheric pressure readings. However, this device is not equipped with complete suite of air quality sensors, what is missing out here are quite substantial and these include volatile organic gas (VOC) , radon, particulate matters , carbon monoxide which are important parameters to determine the air that you breath is safe. And of course to have all these sensors included in an air quality monitor will costs a fortune for regular consumer.
    The Bluetooth range on the Aranet 4 is slightly shorter than inkbird from the distance I tested. 7-8 meters on inkbird vs 6 metres on aranet4.
    aranet 4 has a hidden feature of boosting it's Bluetooth range at presumably small cost of battery life by a toggle under Bluetooth setting of the app to about the same range as inkbird.

    One important thing when placing the double AA battery in, is quite different from other device, make sure you place the positive side first then only negative due to there is a plastic lip at the positive side.
    Battery is super long lasting due to energy efficient E ink display and low energy Bluetooth and especially interval measurement is set to 5 or 10 minutes. Downside to this is that you can only get Bluetooth connection to sync the data to phone rather than wifi and can't assess the data if not in the Bluetooth range or if away from home. Aranet claims there is a smart home integration app called homey but I guess it can be complicated to setup due to the integration is not mainstream like homekit or google home.
    Customer image
    John Danaway Lai
    4.0 out of 5 stars
    Attractive CO2 temperature and humidity monitor. However, app needs some improvement.

    Reviewed in Singapore on May 25, 2024
    Living in a closed space with generally poor ventilation in an apartment, is the reason why I purchase this product. However , after been using it for over 2 weeks now, I have come into conclusion that most of us may not even need it because the CO2 in a closed space in my apartment rarely goes above 800ppm throughout the day. The only situation where it can go above 800ppm is when gas stove is used. However, carbon dioxide monitor or reader can be useful if you live in a rather tight space whereby there are three or more occupants as CO2 is mainly produced by respiration or breathing other than from burning gas. As you can see in the picture here, the screen on the aranet 4 is quite a bit sharper and contrasty than the inkbird and the design is more attractive due to semi transparent plastic case and the underlying board design is partially visible whereas inkbird has a bit of off-white coloration. The measurement is very similar to one another due to similar NDIR sensor used. As mentioned, the main deciding factor whether you need this or not is how many occupants in a space or how crowded the space is. More people occupying same space at same time, the higher the CO2 produced. For the app, I like how you can just drag along the chart to see the reading. However, aranet app only allows 7 days of data to be kept on the device before it gets overwritten where as the inkbird can keep data on the device for up to 30 days. Basically, aranet app is more polished , however, data storage is only limited to 7 days when set to 5 minutes measurement interval instead of 30 days (on device) to 1 year on inkbird (only when is synced to the phone).
    Addendum : Aranet has released a firmware in Dec 2023 that allows you set how long the data can be stored on the device and this depends the measurement interval, i.e. 2 minutes interval equivalent to 7 days of storage; 5 minutes for 15 days ; and 10 minutes for 30 days of storage .
    Besides CO2 readings, you will also get ambient temperature, humidity and atmospheric pressure readings. However, this device is not equipped with complete suite of air quality sensors, what is missing out here are quite substantial and these include volatile organic gas (VOC) , radon, particulate matters , carbon monoxide which are important parameters to determine the air that you breath is safe. And of course to have all these sensors included in an air quality monitor will costs a fortune for regular consumer.
    The Bluetooth range on the Aranet 4 is slightly shorter than inkbird from the distance I tested. 7-8 meters on inkbird vs 6 metres on aranet4.
    aranet 4 has a hidden feature of boosting it's Bluetooth range at presumably small cost of battery life by a toggle under Bluetooth setting of the app to about the same range as inkbird.

    One important thing when placing the double AA battery in, is quite different from other device, make sure you place the positive side first then only negative due to there is a plastic lip at the positive side.
    Battery is super long lasting due to energy efficient E ink display and low energy Bluetooth and especially interval measurement is set to 5 or 10 minutes. Downside to this is that you can only get Bluetooth connection to sync the data to phone rather than wifi and can't assess the data if not in the Bluetooth range or if away from home. Aranet claims there is a smart home integration app called homey but I guess it can be complicated to setup due to the integration is not mainstream like homekit or google home.
    Images in this review
    Customer imageCustomer imageCustomer imageCustomer imageCustomer imageCustomer image
  • LM
    5.0 out of 5 stars Premium quality, works great
    Reviewed in Canada on January 16, 2025
    I love the e-ink screen, the battery life, and the measurements are very accurate. It's a nice touch that you can connect your phone via Bluetooth and look at graphs of the data. It's definitely not cheap but you get a quality device for the price.
  • Monika
    5.0 out of 5 stars Tolles Produkt, funktioniert wie beschrieben
    Reviewed in Germany on July 21, 2024
    Funktioniert wie beschrieben!
    Tolles Produkt, wenn auch preislich sehr hoch!
  • Igor Vallejo
    5.0 out of 5 stars BUENISIMO
    Reviewed in Spain on November 6, 2024
    El mejor sensor de CO2 DEL MERCADO CON DIFERENCIA.
  • Helen Butler
    5.0 out of 5 stars A CO2 monitor that actually works.
    Reviewed in Australia on February 17, 2024
    Love the fact that this monitor actually works. It is small enough to transport in a small bag if needed. Having the app is excellent. It is worth the cost.