SmogRank / History / Country race

Countries, worst air first, day by day

Each country's typical measured city over the 30 days to every day since January 2023, worst first. Press Play to watch the order change, or drag the slider to any day.

CountriesCities
The 30 days to9 Nov 2024 That day's board

The worst countries for PM2.5 over the 30 days to 9 Nov 2024: Pakistan 95.5 µg/m³, India 54.5 µg/m³ and Serbia 35.7 µg/m³.

  1. 1Pakistan4 cities95.5
  2. 2India5 cities54.5
  3. 3Serbia25 cities35.7
  4. 4China3 cities27.2
  5. 5Romania6 cities24.3
  6. 6Thailand16 cities21.6
  7. 7Hungary9 cities20.8
  8. 8Poland73 cities20.7
  9. 9Chile46 cities19.5
  10. 10Slovakia17 cities18.9
  11. 11Peru17 cities18.7
  12. 12Hong Kong13 cities18.0
  13. 13Singapore5 cities15.6
  14. 14Mexico12 cities, was 314.8
  15. 15Bulgaria6 cities12.5
  16. 16South Korea140 cities12.3
  17. 17United Kingdom5 cities, was 6312.0
  18. 18Belgium39 cities11.9
  19. 19Taiwan43 cities11.3
  20. 20Germany226 cities11.1

+ 15 more countries, 10.7 µg/m³ and below

  1. 30United States813 cities7.0

30 days7 days
GoodModerateSensitive groupsUnhealthyVery unhealthyHazardousWHO 24-hour guideline, 15 µg/m³Fades where it stood: not counted that day

A country's number is its typical measured city: the median of its cities' means over the 30 days (a city needs 21 of them measured; 5 of 7 on the 7-day race), shown only with 3 such cities. A country whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air; "was" beside a city count marks a month after many cities joined or left. 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.