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.

The 30 days to1 Jul 2024 That day's board

The worst cities for PM2.5 over the 30 days to 1 Jul 2024: Santa María 107.1 µg/m³, Coyhaique 103.8 µg/m³ and Nacimiento 63.3 µg/m³.

  1. 1Santa MaríaPeru107.1
  2. 2CoyhaiqueChile103.8
  3. 3NacimientoChile63.3
  4. 4Santa Anita - Los FicusPeru61.2
  5. 5DelhiIndia60.3
  6. 6HualpénChile57.0
  7. 7OsornoChile55.0
  8. 8VillarricaChile54.2
  9. 9San CarlosChile54.2
  10. 10CuricóChile53.1
  11. 11PeshawarPakistan52.7
  12. 12N'DjamenaChad52.3
  13. 13RancaguaChile50.0
  14. 14CuranilahueChile48.7
  15. 15TalaganteChile47.5
  16. 16SantiagoChile47.5
  17. 17BaghdadIraq46.5
  18. 18DhakaBangladesh45.9
  19. 19Puerto AysénChile45.8
  20. 20ChillánChile45.4

+ 2,621 more cities, 44.2 µg/m³ and below

Not counted on this day, too few days measured: Rengo since 30 Jun 2024, Quilpué since 22 Jun 2024, Laja since 13 Jun 2024 and 2 more cities.

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.