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 to2 Jun 2023 That day's board

The worst cities for PM2.5 over the 30 days to 2 Jun 2023: Grande Prairie 87.3 µg/m³, Lahore 74.6 µg/m³ and Dhaka 71.5 µg/m³.

  1. 1Grande PrairieCanada87.3
  2. 2LahorePakistan74.6
  3. 3DhakaBangladesh71.5
  4. 4OsornoChile70.3
  5. 5NacimientoChile68.2
  6. 6DelhiIndia58.7
  7. 7CoyhaiqueChile58.0
  8. 8BaghdadIraq57.9
  9. 9LinaresChile57.7
  10. 10Puerto VarasChile55.3
  11. 11CuricóChile54.9
  12. 12SantiagoChile53.5
  13. 13RancaguaChile52.2
  14. 14Fort McMurrayCanada52.2
  15. 15Fort St. JohnCanada50.9
  16. 16TalaganteChile49.9
  17. 17LajaChile49.6
  18. 18San CarlosChile49.5
  19. 19Fort SaskatchewanCanada48.4
  20. 20HyderabadIndia48.0

+ 1,627 more cities, 47.1 µg/m³ and below

Not counted on this day, too few days measured: Kampala since 23 May 2023, Hualpén since 20 May 2023, Shenyang since 13 May 2023 and 37 more cities.

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.