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 7 days to7 Jun 2023 That day's board

The worst cities for PM2.5 over the 7 days to 7 Jun 2023: Bloemfontein 94.4 µg/m³, Nacimiento 79.1 µg/m³ and Dhaka 77.0 µg/m³.

  1. 1BloemfonteinSouth Africa94.4
  2. 2NacimientoChile79.1
  3. 3DhakaBangladesh77.0
  4. 4OsornoChile74.3
  5. 5Rouyn-NorandaCanada73.9
  6. 6TlaquepaqueMexico64.3
  7. 7OttawaCanada63.4
  8. 8Puerto VarasChile63.0
  9. 9New HollandUnited States60.4
  10. 10CoyhaiqueChile59.1
  11. 11KingstonCanada57.8
  12. 12HualpénChile57.4
  13. 13SantiagoChile56.7
  14. 14BethlehemUnited States56.7
  15. 15San CarlosChile56.4
  16. 16TemucoChile55.2
  17. 17AllentownUnited States54.9
  18. 18LahorePakistan54.8
  19. 19RancaguaChile54.7
  20. 20BrakpanSouth Africa54.5

+ 1,775 more cities, 54.4 µg/m³ and below

Not counted on this day, too few days measured: Ash Shīḩānīyah since 5 Jun 2023, Şabāḩ as Sālim since 2 Jun 2023, Ubon Ratchathani since 24 May 2023 and 13 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.