The AQI Hub is a comprehensive online resource dedicated to deepening the public's understanding of their own AQI and AQIs worldwide. The AQI Hub provides detailed descriptions of various national and regional AQI systems, enabling users to understand how an AQI is built and to compare and contrast how different countries assess and communicate air quality. By exploring the methodologies, scales, and health implications associated with each AQI, the AQI Hub empowers individuals to better interpret air quality data, fostering informed decisions about health and environmental protection.