Luftdaten

Luftdaten, or Luftdaten.info, is a citizen science project that creates a global, crowd-sourced network of low-cost air quality sensors. It focuses on measuring particulate matter (PM2.5 and PM10) in the ambient air and, in many installations, collects basic environmental data such as temperature and humidity. The project distributes open hardware and software that volunteers can assemble and deploy, enabling individuals, schools, and communities to monitor local air quality and share results openly.

Originating in Germany in the mid-2010s, Luftdaten grew from a grassroots effort to map air quality with affordable sensors. Participants assemble sensor kits that typically include a microcontroller (such as ESP8266/ESP32 or Raspberry Pi), a particulate matter sensor (for example from Plantower or similar suppliers), and environmental sensors, all housed in a protective enclosure with a sampling inlet. The devices connect to the internet and transmit data to a central server.

Data produced by Luftdaten is made publicly available via an online map and API, allowing researchers, journalists, and the public to view or reuse readings. The project also shares firmware, hardware designs, and installation instructions under open licenses, and works with related platforms such as OpenSenseMap to broaden data access.

While the network has succeeded in raising awareness and providing granular, community-sourced air quality information, it is based on low-cost sensors whose accuracy can vary due to calibration, sensor drift, and installation conditions. Users are advised to consider these factors when interpreting results.