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 to31 Jan 2023 That day's board

The worst cities for PM2.5 over the 30 days to 31 Jan 2023: Lahore 231.0 µg/m³, Dhaka 227.7 µg/m³ and Delhi 194.6 µg/m³.

  1. 1LahorePakistan231.0
  2. 2DhakaBangladesh227.7
  3. 3DelhiIndia194.6
  4. 4N'DjamenaChad169.7
  5. 5PeshawarPakistan128.8
  6. 6DushanbeTajikistan128.2
  7. 7AbujaNigeria116.1
  8. 8BishkekKyrgyzstan106.0
  9. 9MumbaiIndia102.9
  10. 10IslamabadPakistan97.6
  11. 11SalorUzbekistan94.0
  12. 12AlmatyKazakhstan85.9
  13. 13KathmanduNepal81.7
  14. 14HanoiVietnam81.3
  15. 15AlexandriaEgypt74.4
  16. 16HyderabadIndia74.1
  17. 17BaghdadIraq69.5
  18. 18KampalaUganda61.3
  19. 19BamakoMali59.5
  20. 20Banja LukaBosnia and Herzegovina58.2

+ 1,310 more cities, the next at 57.8 µg/m³

Not counted on this day, too few days measured: Niš since 31 Jan 2023 and Lamphun since 31 Jan 2023. Days missing from the source archive fall in this window, so fewer countries are counted.

GoodModerateUnhealthy for sensitive 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, Turkey and Iran, which publish only on their own websites. We are building the reader for China's network. The networks of Turkey and Iran don't answer requests from outside their countries, so we can't read them. Most cities there are missing from this board, not clean. Why.