Real-Time AQI
Live Air Quality Index from thousands of monitoring stations globally.
Pollutant Data
Track PM2.5, PM10, ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2).
Health Advice
Color-coded health recommendations based on current air quality levels.
Wildfire Smoke
Track smoke plumes and air quality impacts from active wildfires.
Air Quality Index (AQI) Scale
- 0-50 Good - Air quality is satisfactory
- 51-100 Moderate - Acceptable; sensitive groups may experience issues
- 101-150 Unhealthy for Sensitive Groups - Children, elderly, and those with respiratory conditions should limit outdoor activity
- 151-200 Unhealthy - Everyone may experience health effects
- 201-300 Very Unhealthy - Health alert; everyone should reduce outdoor activity
- 300+ Hazardous - Emergency conditions; avoid all outdoor activity
Key Pollutants
- PM2.5 - Fine particles (<2.5 micrometers) that penetrate deep into lungs
- PM10 - Coarse particles (<10 micrometers) from dust, pollen
- Ozone (O3) - Ground-level ozone from vehicle/industrial emissions
- NO2 - Nitrogen dioxide from combustion engines
- CO - Carbon monoxide from incomplete combustion
Hazard data sources
Events are aggregated from USGS, EMSC, NOAA, NASA EONET, NASA FIRMS and GDACS, then normalized and deduplicated.
Frequently asked questions
What AQI level is safe?
AQI 0-50 (Green/Good) is safe for everyone. Sensitive groups should be cautious above 100.
How does wildfire smoke affect air quality?
Wildfire smoke dramatically increases PM2.5 levels. Smoke can travel hundreds of miles, affecting air quality far from fires.
Why is air quality worse in the evening?
Temperature inversions trap pollutants near ground level, often occurring in evening/overnight hours. Traffic emissions also peak during commute times.