We spend 80% of our time indoors, where air can be polluted by off-gassing furniture, cooking, and cleaning chemicals. Insufficient ventilation can lead to high CO2 levels, causing headaches, fatigue, and reduced cognitive performance. Measuring indoor air quality helps identify these pollutants, allowing you to create a healthier and more comfortable living environment.Equally important is measuring outdoor air quality. Outdoor pollutants like PM2.5, PM10, and nitrogen dioxide can cause respiratory and cardiovascular issues. These pollutants can enter your home through windows and doors, affecting indoor air quality. By monitoring outdoor air, you can take precautions such as limiting outdoor activities on high-pollution days and improving indoor ventilation.
Understanding indoor and outdoor air quality provides a comprehensive view of the air you breathe. This knowledge allows you to proactively manage your environment, ensuring a safer and healthier space for you and your family. This is especially helpful with Homey, as you can create automation based on differences between indoor and outdoor pollutant levels.
Both AirGradient monitors have an officially supported Homey integration, meaning you can expect a high-quality integration with regular support and updates.
The AirGradient ONE is an indoor air quality monitor with native Homey support.
This monitor measures PM1, PM2.5, PM10, CO2, TVOCs, NOX, temperature and humidity and has a built-in color LED bar and small display.
The AirGradient ONE sends data to your Homey Pro over WiFi, and it’s perfectly suited for monitoring the air quality in kitchens, bedrooms, and living areas inside your home. The Homey platform also allows for easy integration of multiple monitors and automation for monitors and devices in different rooms, allowing you to create a truly smart home.
Our indoor air quality monitor’s enclosure allows it to be mounted on a wall easily or to sit on a desk. Cable routing on the back of the device allows you to manage and hide cables, ensuring the monitor blends in wherever in your house it is placed.
The AirGradient Open Air is a Homey-certified outdoor air quality monitor.
It also measures PM1, PM2.5, PM10, CO2, TVOCs, NOX, temperature, and humidity, allowing you to quickly and easily assess the quality of outdoor air.
Ideally paired with an AirGradient ONE and Homey Pro, these two devices will allow you to identify indoor and outdoor air quality trends and monitor trends between outdoor and indoor air quality. This will give you a full picture of your air quality and can lead to actionable suggestions, such as knowing when to open the windows or when to ‘lockdown’ your home.
The Open Air is fully weather-sealed, meaning it can be mounted on the side of your home or nearby. With a WiFi connection, it can send regular updates to your Homey dashboard and give you further information on your local air quality.
The AirGradient Homey integration makes the setup process seamless. All you need to do is connect your AirGradient monitor to the same network as your Homey Pro, install the AirGradient app from the Homey App Store, and the monitor will automatically be discovered. Then, add the monitor, and you’re ready to integrate!
We’ve noticed a worrying trend in the air quality monitoring industry. Many manufacturers are restricting access to data - even to monitors you own - to monetise it. We couldn’t be more against this approach.
You own all of the data from your AirGradient monitors and can use it however you want. We welcome you to submit the data to Open AQ or the AirGradient map, but the data is yours, and you can use it however you see fit.
AirGradient and Homey Pro can run entirely locally, meaning you don’t need to worry about your data. The monitor will retain full functionality, even if it isn’t connected - you can even manually update the monitor without ever connecting it to the internet.
While many companies try to deceive users by creating lengthy and hard-to-understand terms and conditions, we put ours at the center of our mission. In fact, we encourage you to read our terms and conditions. Long story short: Your monitor and data are yours.
Regardless of what happens to AirGradient, your device is always usable due to its open-source nature. Connecting your monitor to Homey or another platform will ensure it continues operating and never becomes a brick
Whether you want an out-of-the-box Homey-certified air quality monitor or you want to fully use the open-source license and tailor your monitors to exactly your needs, we have a strong and active community that grows daily, where everyone is included and part of a larger movement.
The AirGradient forum facilitates conversations among community members, which has led to bug fixes, device improvements, and even community members creating their own solutions. Our Homey certification requires that we have ongoing support, and much of this is driven by our fantastic community.
Following our open-source beliefs, we welcome all participation on the forum - even in the case of reporting issues with the devices. We appreciate every member who takes the time to share their experiences with AirGradient, and it’s this information that allows us to continue improving our products.
If you use the AirGradient data platform with an AirGradient Open Air, you can opt-in to share your outdoor data with the public and OpenAQ. OpenAQ is a non-profit organisation collecting and organising worldwide air quality data and making it available for the public and research. Your data is then also available on the AirGradient map together with thousands of other monitors from OpenAQ.
This data is freely available for anyone and can go towards improving public health initiatives and even shape policy making. The more accessible air quality data, the better! With the included carbon dioxide sensor, you can also help identify local emissions sources that lead to climate change.
Our air quality monitors come in a DIY kit or prebuilt configuration. The DIY kit allows you to save money by assembling the monitor yourself - it’s also a great way to learn about the inner workings of your open-source monitor.The DIY kits are easy to build (no soldering required), and everything required is inside the box. With the manual, you can assemble your DIY monitor and integrate it with your Homey Pro in under 15 minutes. You can contact us directly or ask on our forum if you run into issues.
We also offer both monitors in a pre-built configuration that comes ready to integrate with Homey out of the box. This monitor also comes with a one-year warranty, multiple certifications, and a lab test report, which we provide to ensure the components and monitor are working very accurately.
At AirGradient, we emphasize science, ensuring we use only high-quality components that are performant and accurate. However, some components have finite lifespans, meaning they need to be replaced eventually. To overcome this, we’ve built our monitors with repairability and long-term use in mind.All components in AirGradient monitors can be purchased individually, meaning that if a component fails, there is no need to replace the whole monitor - just the faulty part. In the case of non-AirGradient parts, these replacement parts can be purchased either from us or from a local distributor.
This combination of open-source hardware and software ensures that your AirGradient monitor will provide air quality insights for many years to come.
Both homey-enabled monitors use high-quality sensors from industry leaders like SenseAir, Sensirion, and Plantower, ensuring accuracy through rigorous testing and calibration.
The SenseAir S8 CO2 sensor utilizes NDIR technology with automatic baseline calibration (ABC) every seven days (customizable), providing very accurate measurements. High levels of CO2 can indicate poor ventilation, causing headaches, tiredness, and reduced cognitive performance. Increasing outdoor CO2 levels can be indicators of climate change.
For PM2.5 measurements, AirGradient employs the Plantower PMS5003(T) sensors, which use laser scattering technology and have been extensively tested in various studies. Elevated PM2.5 levels are linked to numerous health issues, including premature mortality, heart or lung problems, and asthma attacks. The sensor module is factory-calibrated.
TVOCs and NOX are measured with the Sensirion SGP41 sensor, which detects volatile organic compounds from indoor sources like off-gassing furniture, aggressive cleaning liquids, and harmful gases from gas stoves or boilers. Outdoors they can be emitted by vehicles and indicate areas of high pollution. The measurements are based on the Sensirion VOC Index, which represents changes in VOC concentrations. Temperature and humidity are measured with the Sensirion SHT3x/4x sensors, known for their accuracy and for providing insights into indoor comfort levels and mold risk.
We work very closely with several leading universities on air quality monitoring, and due to its performance and affordability, our indoor air quality monitor has been selected for the largest study of classroom air quality in the world. We also work on many co-location projects with our outdoor air quality monitor and leading universities worldwide. You can read more about our work with research institutions on our research page.
Both monitor’s open-hardware / open-source nature allows easy changes and additions to the firmware and hardware. The board is powered by an ESP32-C3-MINI microcontroller that is easy to program with a wide ecosystem and has integrated WiFi and Bluetooth capabilities.
The ESP32 can be directly flashed through the USB C port, making changes in the open-source firmware easy.
For those who would like to adjust the monitor, breakout pins are available for I2C and three additional IOs. In addition, you can repurpose the two UARTs. The board provides both 5 and 3.3 volts.
We integrated an external hardware watchdog chip that automatically reboots the unit in case something goes wrong, enabling the monitor to achieve high uptimes.
Below is the technical data of the newest version of the AirGradient ONE. Available in our online store.
Specification | Description |
---|---|
Model | I-9PSL (AirGradient ONE, 9th Generation) |
Microcontroller | ESP32-C3-MINI (32-bit RISC-V single-core processor, up to 160MHz, 384 KB ROM, 400 KB SRAM, 8 KB SRAM in RTC, 4 MB flash in chip package) |
WiFi | 2.4GHz IEEE 802.11 b/g/n-compliant |
Display | OLED display 1.3 inch (I2C 128x64px) |
Bluetooth | Bluetooth LE: Bluetooth 5, Bluetooth mesh |
Extensions | Broken out on PCB: I2C, 3 GPIO, 2 UART |
Peripherals | 11 RGB-LEDs, Push Button, Reset Button, USB C Connector |
External Hardware Watchdog | Texas Instruments TPL5010 |
CO2 Sensor Module | SenseAir S8 (NDIR). 0 to 10000ppm. Accuracy: ±40 ppm ±3% of reading at 5 to 30°C, 0-85% RH (400 - 2000ppm range) |
Particle Sensor Module | Plantower PMS5003 (laser scattering principle). Accuracy: ±10%@100~500μ g/m³, ±10μg/m³@0~100μ g/m³ |
Temperature and Humidity Module | Sensirion SHT40. Accuracy: Temperature ±0.2°C @ -40 to + 125°C; Humidity ±2% RH @ 0 - 100% RH |
TVOC/NOX Module | Sensirion SGP41. Accuracy: TVOC <±15 @ 0 to 500 VOC Index; NOX <±50 @ 0 - 500 NOX Index |
Enclosure | ASA Plastic, UV Resistant and Weather Proof |
Cable | 2m USB C Cable including Data Lines for Flashing |
Power Plug (not included) |
|
Dimensions & Weight | 130 x 130 x 35mm, 350 grams |
Certifications | CE, RoHS, REACH, RESET Air, FCC ID: 2AC7Z-ESPC3MINI |
Below is the technical data of the default version of the Open Air as it is available in our online store.
Specification | Description |
---|---|
Model | O-1PST (AirGradient Open Air) |
Microcontroller | ESP32-C3-MINI (32-bit RISC-V single-core processor, up to 160MHz, 384 KB ROM, 400 KB SRAM, 8 KB SRAM in RTC, 4 MB flash in chip package) |
WiFi | 2.4GHz IEEE 802.11 b/g/n-compliant |
Bluetooth | Bluetooth LE: Bluetooth 5, Bluetooth mesh |
Extensions | Broken out on PCB: I2C, 3 GPIO, 2 UART |
Peripherals | Status LED, Push Button, USB C Connector |
External Hardware Watchdog | Texas Instruments TPL5010 |
Particle Sensor Module | Plantower PMS5003T (laser scattering principle). Accuracy: ±10%@100~500μ g/m³, ±10μg/m³@0~100μ g/m³ |
Temperature and Humidity | ENS210 (inside PMS5003T module). Accuracy: Temperature ±0.2°C @ 0 - 70°C; Humidity ±3.5% RH @ 20 - 80% RH |
CO2 Sensor Module | SenseAir S8 (NDIR). 0 to 10000ppm. Accuracy: ±40 ppm ±3% of reading at 5 to 30°C, 0-85% RH (400 - 2000ppm range) |
TVOC/NOX Module | Sensirion SGP41. Accuracy: TVOC <±15 @ 0 to 500 VOC Index; NOX <±50 @ 0 - 500 NOX Index |
Enclosure | ASA Plastic, UV Resistant and Weather Proof |
Mounting Options | Wall or pole mounting options |
Cable | 4m USB C Cable including Data Lines for Flashing |
Power Plug (not included) |
|
Certifications | CE, RoHS, REACH, FCC ID: 2AC7Z-ESPC3MINI |
We are blessed to have such an active community. Read more about community engagement.
More articles on our blog.
We are very thankful for the overwhelming support we get for the AirGradient air quality monitors and are especially thankful for people that write about their experiences using the monitors. Below is a wide range of reviews from AirGradient users!
My Smart Home recently covered the AirGradient Open Air and ONE, focusing on harnessing these devices’ full power through the automation made possible with Home Assistant. Learn the full power of AirGradient and Home Assistant in his full video.
Mike from the Gadgeteer set up an AirGradient ONE inside their 3D printing workshop and used the monitor to discover how much 3D printing impacts air quality and how it can be improved.
Brian set up the AirGradient Open Air and implemented it with Home Assistant, highlighting how straightforward the setup process is and how powerful the integration is.
Smart Home Circle provided a detailed guide on how to set up and operate the monitor, including integrating it with Home Assistant for enhanced smart home control. The video highlights the monitor’s ease of use and its role in maintaining indoor air quality awareness.
Reed from Smart Home Solver tested multiple air quality monitors and chose the AirGradient ONE as his top pick for improving the air quality around his home and office. He also loved the Home Assistant integration and our open-source approach.
TechStage reviewed the AirGradient ONE and praised it as a ‘powerful and affordable open-source air quality monitor. ’ It highlighted its ability to measure CO₂, fine dust, TVOCs, and NOx and its seamless integration into Home Assistant and Homey Pro for smart home automation.
TechStage reviewed the Open Air and has this to say: It’s a responsive and affordable open-source outdoor air quality monitor measuring CO₂, fine dust, TVOCs, and NOx, with seamless integration into Home Assistant and Homey Pro for smart home automation.
In a review by SlimothyTV, the AirGradient ONE was praised for its eco-friendly design, open-source approach, and seamless performance. Slim highlighted its affordability, sustainability, and integration with smart home systems, calling it ‘incredibly powerful’.
Danny from HouseFresh praised AirGradient’s indoor and outdoor sensors for their open-source design, accurate high-end sensors, and user-friendly dashboard. The reviewer highlighted AirGradient’s clear data ownership policy and ease of use.
Irish Tech News discusses how a combination of the AirGradient ONE and Open Air allowed them to take actionable steps to improve the air quality in their office.
The team at PcDeMaNo recently tried both the AirGradient ONE and Open Air, going so far as to say that ‘AirGradient + HomeAssistant is the perfect match’. They also awarded the monitors a 9.75/10 rating.
With the official release of Home Assistant integration on AirGradient monitors, Simon delves into the powers of the platform, showing the capabilities of the AirGradient Open Air when combined with the home automation platform.
BBC Newsround featured our indoor monitor that is used in the SAMHE project (Schools’ Air quality Monitoring for Health and Education). The video report provides exhaustive information on the project itself and AirGradient monitors role in it.
An article analysing the accuracy of monitors from USD 100 to a few thousand got featured by Hackaday: The Questionable Benefits of Paying More for Air Quality Monitors.
Our monitors were selected to be the core part of the SAMHE project, the largest study on classroom air in the world. A big part of this project is to increase the awareness of healthy air among primary and secondary students.
Ethan from BreatheSafeAir wrote a very comprehensive review of the AirGradient Open Air, where he compared different monitors models.
See the conversation Jeff has with his dad about the importance of indoor air quality monitoring and their opinion of the AirGradient monitor: An ACTUALLY smart air quality monitor (it’s open) .
Tyler built the AirGradient to measure smoke from the Canadian Wildfires and also makes has some interesting links in his article, e.g. how air pollution makes chess players make more errors.
In his in-depth review on our indoor DIY kit Igor highlights its affordability, accuracy, and open-source nature. Reading this review is a delight thanks to the author’s engaging style, coupled with the informative content and great images.
We are a huge fan of Jeff Geerling YouTube Videos, and he made a fantastic video review when we had only our first air quality kit, the Basic kit. It’s great that he also talks what actually made him want to know more about the air quality in his basement office.
Igor purchased and reviewed our indoor DIY kit and we liked his unbiased review on our indoor monitor so much that we gave him two outdoor monitors with the hope that he would also write about them. And it actually happened!
Very in-depth review of the new AirGradient ONE kit with the ESP32-C3 microcontroller: AirGradient ONE Kit Review – An open-source indoor air quality monitor.
Many thanks to Nicholas who reviewed our indoor and outdoor open hardware kits and wrote about his reasons to know about the air he breathes. By the way, we made some changes on the outdoor enclosure and the assembly is much easier now.
Sotirios not only wrote about our basic kit but also about our open sourced small information display that is particularly popular with student projects in schools.
Daniel Persson talks about how he build an AirGradient and could actually now see how fast CO2 increases indoors.
This is a great technical review how Yosua setup our open hardware indoor monitor with his own server based on home assistant.
There are some great programming notes on Thatcher’s blog that covers also his ESPHome installation.
We are proud being official partner to OpenAQ and they wrote about our partnership on their blog.
We talked about the importance of monitoring air quality and the work we do at AirGradient with the Stockholm Environment Institute Asia Centre.
Andrej has a small home office (14 square meters) and build an AirGradient to find out how is the air quality in his home office.
If you like our open hardware monitors please spread the news and consider writing a review about them! Since our monitor designs are open and under Creative Common license, and we want honest and unbiased reviews it is against our ethos to pay for reviews. But we would be very happy to support in other ways.
This manifesto reflects our core values and the principles we stand for:
We must be bold. We always follow our convictions and call out the issues that matter, sharing our views on topics surrounding air quality and environmental responsibility. We will not compromise for profit. We believe that open, informed, and candid discussions are the catalysts for meaningful change. We will lead by example and become a driving force for environmental monitoring.
We will deliver benefits for both people and the planet. This is why we prioritise creating high-quality air quality monitors with designs that enable easy repairs and recycling, thereby extending the product’s lifespan and reducing its environmental footprint.
Our research is driven by a commitment to environmental protection, not by profits. This is why we don’t patent our air quality monitor designs but on the contrary, share them openly, allowing everyone to build them and to contribute to positive change. We do not lock users into proprietary eco-systems and we encourage sharing of air quality data and algorithms as a public good.
We want to raise awareness about air pollution through active community building with a strong focus on informing about the dangers of air pollution. We actively support environmental justice organisations and educational institutions in their missions to provide healthier environments for everyone.
To deliver positive impacts on the communities, and the environment, we must sustain our business model. However we will not prioritise profits above our convictions. We embed this rationale into our everyday decision-making processes throughout all layers of our company. (e.g. by joining 1% for the Planet).
AirGradient is built on a foundation of openness and inclusivity. We aim to make our products and services available to a wide range of users with a special focus on underrepresented communities. We strive to work with all organisations that want to make a positive contribution independent of their financial means.
Curious about upcoming webinars, company updates, and the latest air quality trends? Sign up for our weekly newsletter and get the inside scoop delivered straight to your inbox.
Join our Newsletter