Description
AirGradient One Indoor Air Monitoring Kit (Unassembled)
NOTE: The kit has the exact same hardware as the fully assembled version above but needs to be self-assembled. It's a fun and straightforward project for people who enjoy assembling electronics kits. Please note the following differences from the assembled AirGradient One:
- No warranty (because something might break during the assembly)
- No certifications and test report
The AirGradient ONE (Model I-9PSL) is an indoor air quality monitor enabling you to know if the air quality is healthy or not. It measures PM 2.5, CO2, TVOCs, NOX, Temperature and Humidity and has a built-in color LED bar and small display. It’s fully open-source and customizable, with native Home Assistant and Homey support.
Why Indoor Air Quality Matters
We spend 80% of our time indoors, and the indoor air is often polluted not only from sources outside your home but also from indoor pollutants like off-gassing furniture, cooking, and cleaning chemicals. Houses with insufficient fresh air ventilation can have very high CO2 levels that can cause headaches and tiredness and greatly impact cognitive performance. Measuring these parameters helps you identify pollutants and create a healthy, comfortable indoor environment.
Key Characteristics
AirGradient uses high-quality sensor modules from industry leaders like SenseAir, Sensirion, and Plantower. Every sensor goes through multi-step testing and calibration for high accuracy.
- CO2: SenseAir S8/S88 (NDIR) with automatic baseline calibration (ABC).
- PM 2.5: Plantower PMS5003 (laser scattering), widely tested in independent studies.
- TVOCs & NOX: Sensirion SGP41 using the Sensirion VOC Index (relative changes over time).
- Temp & Humidity: Sensirion SHT3x/4x for comfort and mold-risk insights.
- On-device UX: 1.3" OLED display plus 11 RGB LEDs (configurable).
Flexible Data Platforms & Smart Home Support
Being open-source, you’re never locked into one platform. Use the purpose-built AirGradient platform or connect to your own server. The community offers extensions for ESPHome, Prometheus, openHAB, and more. From Home Assistant 2024.6 onwards (latest firmware), AirGradient ONE is discovered natively; Homey is supported via the marketplace app.
Try the AirGradient Dashboard now!
Track, analyze, and visualize air quality for multiple locations, set alerts, and receive daily/weekly reports. No monitor required for the demo. Launch the demo.
Mounting Options
Mount on a wall or place on a desk with optional clip-on stands. Wall-mount screw spacing fits common EU/US junction boxes. USB-C cable connects at the back; routing can be from top or bottom.
Easy to Assemble, Setup & Install
The kit version is easy to assemble with detailed guides and videos. Connect it to Wi-Fi, the dashboard, and the map. Get help directly from AirGradient or the community forum.
RESET-Accredited & USGBC Member
The AirGradient ONE is designed to align with building standards. It is RESET-accredited, and AirGradient is a member of the USGBC.
Optimized Enclosure
Designed for accurate airflow and minimal condensation risk, using robust, UV-resistant ASA plastic for durability.
Get the AirGradient ONE
- Model I-9PSL
- Sensors for CO2, PM 2.5, TVOCs, NOX, Temperature & Humidity
- 2m USB-C cable (w/o power plug)
- 12 months data platform / dashboard and API access (or connect to your own server, e.g., Home Assistant)
- Local Home Assistant support with auto-discovery
- Fully open-source code
- Fully assembled & tested (chamber test report)
- Certified: CE, FCC, RoHS, REACH, RESET Air
- 12 months warranty
Also available as a kit (same hardware) with differences in warranty/certifications due to self-assembly.
Technical Data
| Model | I-9PSL (AirGradient ONE, 9th Gen) |
| Microcontroller | ESP32-C3-MINI (RISC-V up to 160 MHz, 4 MB flash) |
| Wi-Fi | 2.4 GHz IEEE 802.11 b/g/n |
| Display | 1.3" OLED (I2C 128×64) |
| Bluetooth | Bluetooth LE 5 / mesh |
| Extensions | Breakouts: I2C, 3×GPIO, 2×UART |
| Peripherals | 11 RGB-LEDs, Push Button, Reset Button, USB-C |
| External Watchdog | TI TPL5010 |
| CO2 Sensor | SenseAir S8 or S88 (NDIR) 0-10000 ppm |
| Particle Sensor | Plantower PMS5003 (PM1, PM2.5, PM10) |
| Accuracy (PM 2.5) | Assembled: ±4 μg/m³ (0-100) / ±8% (100-500); Kit: ±10 μg/m³ (0-100) / ±10% (100-500) |
| T/RH Module | Sensirion SHT40 (±0.2 °C; ±2% RH) |
| TVOC/NOX Module | Sensirion SGP41 (VOC Index, NOX Index) |
| Enclosure | ASA Plastic, UV-resistant |
| Cable | 2 m USB-C to USB-A (with data lines) |
| Power | Require >2A 5V USB-A power plug (not included) |
| Dimensions & Weight | 130 × 130 × 35 mm; ~350 g |
| Certifications | CE, RoHS, REACH, RESET Air, FCC ID: 2AC7Z-ESPC3MINI |
Download specification sheet (PDF)
Winner Most Accurate Multi-Pollutant Sensor
The AirGradient ONE received two awards at the AIRLAB Microsensors Challenge 2023:
- Most Accurate Multi-Pollutant Indoor Air Quality Monitoring under €500
- Best Accuracy for PM 2.5 Sensors indoors under €500
Ideally Combined with an Outdoor Monitor
Pair the indoor monitor with an outdoor monitor for full context—source tracking, ventilation insight, and combined reports in the AirGradient dashboard. Learn more on the outdoor monitor page.
Open Hardware – Easy to Extend
Powered by ESP32-C3-mini with integrated Wi-Fi & Bluetooth. Direct flashing over USB-C, breakout pins for I2C and extra I/Os, and an external hardware watchdog for high uptime.
Reviews
Additional Resources