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 to21 Apr 2023 That day's board

The worst cities for PM2.5 over the 7 days to 21 Apr 2023: Dhaka 110.5 µg/m³, Kathmandu 106.2 µg/m³ and Bamako 74.4 µg/m³.

  1. 1DhakaBangladesh110.5
  2. 2KathmanduNepal106.2
  3. 3BamakoMali74.4
  4. 4Bang Khun ThianThailand68.6
  5. 5DelhiIndia64.5
  6. 6HyderabadIndia63.0
  7. 7BeijingChina59.9
  8. 8HanoiVietnam55.9
  9. 9TlaquepaqueMexico55.3
  10. 10San Mateo AtencoMexico54.5
  11. 11Nong KhaemThailand54.2
  12. 12Nakhon PathomThailand53.1
  13. 13LahorePakistan52.9
  14. 14Samut PrakanThailand52.2
  15. 15BangkokThailand51.2
  16. 16YangonMyanmar48.1
  17. 17Samut SakhonThailand47.6
  18. 18Phra PradaengThailand46.7
  19. 19Mueang NonthaburiThailand46.3
  20. 20Khlong LuangThailand46.1

+ 1,684 more cities, 45.9 µg/m³ and below

Not counted on this day, too few days measured: Dushanbe since 21 Apr 2023, Manama since 20 Apr 2023, Tha Bo since 17 Apr 2023 and 48 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.