ENS160 Air Quality Sensor (CCS811 Upgrade) — TVOC, eCO2 & AQI over I2C

The Adafruit ENS160 MOX Gas Sensor is a modern replacement for the discontinued CCS811, built for quick indoor air-quality projects. It provides sensor-fusion outputs like TVOC, eCO2, and AQI over I2C, and comes in the STEMMA QT / Qwiic form factor for easy, solderless wiring.

What you can build

• Indoor air-quality monitor (home/office/classroom)
• VOC trend monitor to trigger fans/ventilation
• “Digital nose” demo (odor / alcohol vapor spikes)

Technical specifications

Pinout & power notes

• Use I2C SDA/SCL to your microcontroller’s I2C pins.
• Designed to be friendly with both 3.3V and 5V systems (regulator + level shifting onboard).
• For best accuracy, you can add temperature/humidity compensation by sending RH% from an external humidity sensor.

What’s in the box

• 1x ENS160 STEMMA QT / Qwiic breakout board
• STEMMA QT cable typically sold separately (optional add-on)

FAQ

• Is this a CCS811 replacement?
  Yes—similar use-case, but it requires new driver/library code.
• Is it accurate for absolute ppm/ppb readings?
  Like most gas/VOC sensors, it’s best for trends unless calibrated against known references.
• What is the I2C address?
  0x53 (fixed, cannot be changed).
• Do I need other sensors?
  Optional: add a humidity sensor if you want temp/RH compensation for better stability.