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 to18 Jun 2024 That day's board

The worst cities for PM2.5 over the 30 days to 18 Jun 2024: Coyhaique 124.1 µg/m³, Santa María 110.7 µg/m³ and N'Djamena 98.2 µg/m³.

  1. 1CoyhaiqueChile124.1
  2. 2Santa MaríaPeru110.7
  3. 3N'DjamenaChad98.2
  4. 4OsornoChile78.8
  5. 5NacimientoChile73.9
  6. 6DelhiIndia67.4
  7. 7Santa Anita - Los FicusPeru63.4
  8. 8HualpénChile62.6
  9. 9CuricóChile60.6
  10. 10RengoChile59.2
  11. 11DhakaBangladesh58.5
  12. 12San CarlosChile58.0
  13. 13CuranilahueChile57.6
  14. 14Puerto VarasChile56.1
  15. 15La UniónChile54.9
  16. 16RancaguaChile52.6
  17. 17TalaganteChile50.7
  18. 18Puerto AysénChile50.7
  19. 19SantiagoChile50.1
  20. 20ChillánChile49.7

+ 2,630 more cities, 48.9 µg/m³ and below

Not counted on this day, too few days measured: Laja since 13 Jun 2024, Lahore since 7 Jun 2024 and Tlaquepaque since 23 May 2024.

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.