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 7 days to27 Jan 2025 That day's board

The worst cities for PM2.5 over the 7 days to 27 Jan 2025: Dhaka 248.1 µg/m³, Kolkata 176.2 µg/m³ and Lahore 161.9 µg/m³.

  1. 1DhakaBangladesh248.1
  2. 2KolkataIndia176.2
  3. 3LahorePakistan161.9
  4. 4N'DjamenaChad126.8
  5. 5KampalaUganda124.6
  6. 6MumbaiIndia104.8
  7. 7DelhiIndia104.7
  8. 8Banja LukaBosnia and Herzegovina99.7
  9. 9SarajevoBosnia and Herzegovina96.2
  10. 10KathmanduNepal92.9
  11. 11KarachiPakistan87.3
  12. 12IslamabadPakistan78.0
  13. 13Nong KhaemThailand74.8
  14. 14ShenyangChina74.3
  15. 15Khan Na YaoThailand74.3
  16. 16Bueng KumThailand74.1
  17. 17Ulan BatorMongolia73.7
  18. 18Nong ChokThailand73.0
  19. 19Khlong Sam WaThailand72.5
  20. 20Bang NaThailand72.2

+ 2,647 more cities, 72.1 µg/m³ and below

Not counted on this day, too few days measured: Dhahran since 20 Jan 2025, Negotin since 19 Jan 2025, Lagos since 19 Jan 2025 and 5 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.