AQI Comparison
AQI 50 vs AQI 165
A one-step AQI category change can mean a meaningful increase in estimated PM2.5 concentration-time.
AQI 50
0.41
cigarette-equivalents per 24h
Good: Most people can keep their normal routine.
AQI 165
3.43
cigarette-equivalents per 24h
Unhealthy: Everyone should start taking protective steps, not just sensitive groups.
What changes between these two AQI values
Difference in PM2.5
66.5
µg/m³
Difference per day
3.02
cigarettes
Direction
AQI 165 is materially heavier exposure
Moving from AQI 50 to AQI 165 changes both estimated PM2.5 concentration and the protection plan.
Calculate AQI 50
Open the interactive calculator with AQI 50 loaded.
Calculate AQI 165
Use the interactive calculator to test a different duration.
See how the numbers are derived
Review the AQI-to-PM2.5 and PM2.5-to-cigarettes methodology.