Purple Air pioneered low-cost PM monitors, widely studied and accepted. Comparing popular models like Classic and Flex to AirGradient Open Air, data shows similar accuracy. Purple Air offers better map functionality, RGB LED, and SD card storage. AirGradient offers additional sensor modules, open-source/open data license, and lower prices. Purple Air restricts data use, while AirGradient allows unrestricted ownership. Both models use Plantower PM modules. Contact AirGradient for questions. Disclaimer: as a monitor manufacturer, AirGradient is biased, but aims to provide fair and objective comparisons due to being an open-source hardware company. Overall, Purple Air and AirGradient have similar accuracy with unique features and different pricing models.
https://www.airgradient.com/blog/airgradient-vs-purple-air/