Hamilton County, Illinois
AQI 43 · Good43
Median AQI
62
90th Percentile
98
Max AQI
269
Days with Data
Ranked #10 of 23 counties in Illinois (by median AQI, lower is better)
Monthly Median AQI — 2025
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43
Median AQI
62
90th Percentile
98
Max AQI
269
Days with Data
Ranked #10 of 23 counties in Illinois (by median AQI, lower is better)
Click a bar to view that month's details