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.

The 30 days to7 Jun 2026 That day's board

The worst countries for PM2.5 over the 30 days to 7 Jun 2026: Chile 49.2 µg/m³, Pakistan 39.1 µg/m³ and India 32.5 µg/m³.

  1. 1Chile46 cities49.2
  2. 2Pakistan14 cities39.1
  3. 3India222 cities32.5
  4. 4Peru6 cities26.0
  5. 5Malawi5 cities19.3
  6. 6Mexico41 cities17.0
  7. 7South Korea134 cities14.3
  8. 8Kazakhstan4 cities13.9
  9. 9Senegal4 cities13.9
  10. 10Laos3 cities13.8
  11. 11Lebanon3 cities13.8
  12. 12Thailand79 cities13.2
  13. 13New Zealand6 cities11.9
  14. 14Taiwan44 cities11.5
  15. 15Malta5 cities11.2
  16. 16Serbia8 cities10.4
  17. 17Martinique3 cities10.3
  18. 18Brazil6 cities10.0
  19. 19Italy37 cities, was 99.0
  20. 20Greece9 cities8.9

+ 26 more countries, 8.7 µg/m³ and below

  1. 31United States861 cities5.9

Not counted on this day, too few cities measured: Hong Kong since 7 Jun 2026, Latvia since 7 Jun 2026, Slovenia since 19 May 2026 and 3 more countries.

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.