SmogRank / Countries / United States / Illinois

Most polluted cities in Illinois, United States

26 measured cities, last 24 hours; 8 above the WHO 24-hour guideline. Worst: Wheaton at 25.6 µg/m³, #43 in the world.

1 good  25 moderate

  1. 1Wheatonlow-cost sensors 25.61.7×
  2. 2Granite City 18.61.2×
  3. 3Peoria 17.01.1×
  4. 4Evanstonlow-cost sensors 16.21.1×
  5. 5Franklin Park 16.01.1×
  6. 6Calumet City 15.71.0×
  7. 7Upper Alton 15.41.0×
  8. 8Decatur 15.11.0×
  9. 9East Saint Louis 14.91.0×
  10. 10Evergreen Parklow-cost sensors 14.41.0×
  11. 11Bloomington 14.00.9×
  12. 12Brookfield 13.40.9×
  13. 13Oak Lawn 13.40.9×
  14. 14Northbrook 13.30.9×
  15. 15Bridgeview 13.10.9×
  16. 16Chicago 12.60.8×
  17. 17Naperville 12.30.8×
  18. 18Dolton 11.90.8×
  19. 19Elmwood Park 11.80.8×
  20. 20Rockford 11.80.8×
  21. 21Elgin 11.20.7×
  22. 22Zion 10.80.7×
  23. 23Aurora 10.20.7×
  24. 24Des Plaines 9.70.6×
  25. 25Moline 9.10.6×
  26. 26Cary 8.90.6×
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+

Estimated: cities without a monitor

Illinois cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.

City7-day estimateBand
North Peoria≈ 6 µg/m³Good
Waukegan≈ 5 µg/m³Good
Cicero≈ 7 µg/m³Good
Arlington Heights≈ 9 µg/m³Good
Schaumburg≈ 8 µg/m³Good
Bolingbrook≈ 9 µg/m³Good
Palatine≈ 9 µg/m³Good
Orland Park≈ 9 µg/m³Good
Tinley Park≈ 8 µg/m³Good
Berwyn≈ 7 µg/m³Good
Mount Prospect≈ 9 µg/m³Good
Normal≈ 6 µg/m³Good
Oak Park≈ 7 µg/m³Good
Hoffman Estates≈ 8 µg/m³Good
Downers Grove≈ 9 µg/m³Moderate
Glenview≈ 7 µg/m³Good
Elmhurst≈ 9 µg/m³Moderate
Lombard≈ 9 µg/m³Moderate
DeKalb≈ 7 µg/m³Good
Plainfield≈ 8 µg/m³Good
Urbana≈ 6 µg/m³Good
Belleville≈ 6 µg/m³Good
Bartlett≈ 8 µg/m³Good
Buffalo Grove≈ 9 µg/m³Good
Quincy≈ 7 µg/m³Good
Streamwood≈ 8 µg/m³Good
Crystal Lake≈ 6 µg/m³Good
Carol Stream≈ 8 µg/m³Good
Romeoville≈ 9 µg/m³Good
Rock Island≈ 8 µg/m³Good
Carpentersville≈ 8 µg/m³Good
Hanover Park≈ 8 µg/m³Good
Wheeling≈ 9 µg/m³Good
Addison≈ 9 µg/m³Moderate
Glendale Heights≈ 8 µg/m³Good
Oswego≈ 8 µg/m³Good
Woodridge≈ 9 µg/m³Good
Elk Grove Village≈ 9 µg/m³Good
Pekin≈ 5 µg/m³Good
St. Charles≈ 8 µg/m³Good

Updated 2026-10-01 23:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.