SmogRank / History / City race

Cities, worst air first, day by day

Each measured city's average over the 30 days to every day since January 2023, worst first. Find your own city to follow it through the race, or keep to one country.

CountriesCities
The 30 days to21 Jan 2023 That day's board

The worst cities for PM2.5 over the 30 days to 21 Jan 2023: Pristina 54.7 µg/m³, Saint Paul 17.8 µg/m³ and Minneapolis 16.7 µg/m³.

  1. 1PristinaKosovo54.7
  2. 2Saint PaulUnited States17.8
  3. 3MinneapolisUnited States16.7
  4. 4Apple ValleyUnited States16.5
  5. 5NairobiKenya16.3
  6. 6La CrosseUnited States15.4
  7. 7PhoenixUnited States15.0
  8. 8RedfordUnited States14.7
  9. 9Saint CloudUnited States14.0
  10. 10ClintonUnited States13.8
  11. 11Eau ClaireUnited States13.8
  12. 12NogalesMexico13.4
  13. 13KalamazooUnited States13.3
  14. 14IndianapolisUnited States13.2
  15. 15DearbornUnited States13.2
  16. 16DetroitUnited States13.0
  17. 17GreeleyUnited States13.0
  18. 18DavenportUnited States12.8
  19. 19MolineUnited States12.8
  20. 20Calumet CityUnited States12.6

+ 182 more cities, 12.5 µg/m³ and below

Days missing from the source archive fall in this window, so fewer countries are counted.

30 days7 days
GoodModerateSensitive groupsUnhealthyVery unhealthyHazardousWHO 24-hour guideline, 15 µg/m³Fades where it stood: not counted that day

A city's number is its average over the 30 days, shown only when 21 of them were measured (5 of 7 on the 7-day race), the same minimum as the 30- and 7-day boards. A city whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air. Some large countries are thin or missing because their monitors' licences don't allow reuse. How we rank.

Not covered: the government monitoring networks of China and Turkey, which publish only on their own websites; we are building the readers for them. Most cities there are missing from this board, not clean. Why.