AQI Comparison

AQI 50 vs AQI 250

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 250

7.95

cigarette-equivalents per 24h

Very Unhealthy: This is an indoor-air-management problem, not just an outdoor comfort problem.

What changes between these two AQI values

Difference in PM2.5

165.9

µg/m³

Difference per day

7.54

cigarettes

Direction

AQI 250 is materially heavier exposure

Moving from AQI 50 to AQI 250 changes both estimated PM2.5 concentration and the protection plan.

Calculate AQI 50

Open the interactive calculator with AQI 50 loaded.

Calculate AQI 250

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.

Compare with common AQI benchmarks