Denmark City AQI Comparison
Rank cities side by side using OpenAQ PM2.5 and PM10 history normalized to US EPA AQI. This pilot covers 7 eligible cities with OpenAQ-derived daily AQI history.
Compare two cities
vs
Featured comparisons
Aalborg vs Copenhagen→
Highest vs cleanest city
AQI gap 20104 / 117 days
Aalborg vs Lystrup→
Highest-AQI pair
AQI gap 4104 / 78 days
Aalborg vs Silkeborg→
High vs mid-range city
AQI gap 16104 / 23 days
Lystrup vs Copenhagen→
Second-highest vs cleanest city
AQI gap 1678 / 117 days
Silkeborg vs Jyllinge→
High vs low-AQI city
AQI gap 323 / 96 days
Lystrup vs Jyllinge→
High vs low-AQI city
AQI gap 1578 / 96 days
Lystrup vs Silkeborg→
Similar high-AQI cities
AQI gap 1278 / 23 days
Jyllinge vs Copenhagen→
Similar high-AQI cities
AQI gap 196 / 117 days
Methodology
The extractor maps OpenAQ monitoring locations to the nearest AQI Now city in the same country, aggregates PM2.5 and PM10 to daily city averages, and converts those concentrations to US EPA AQI. Country tool pages use only city summaries that satisfy the configured minimum daily coverage threshold.