King County, Washington
AQI 43 · Good43
Median AQI
61
90th Percentile
90
Max AQI
243
Days with Data
Ranked #30 of 31 counties in Washington (by median AQI, lower is better)
Monthly Median AQI — 2025
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43
Median AQI
61
90th Percentile
90
Max AQI
243
Days with Data
Ranked #30 of 31 counties in Washington (by median AQI, lower is better)
Click a bar to view that month's details