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 to11 Jun 2026 That day's board

The worst countries for PM2.5 over the 30 days to 11 Jun 2026: Chile 50.6 µg/m³, Pakistan 35.0 µg/m³ and India 32.8 µg/m³.

  1. 1Chile46 cities50.6
  2. 2Pakistan14 cities35.0
  3. 3India222 cities32.8
  4. 4Peru6 cities26.0
  5. 5Malawi5 cities20.9
  6. 6Mexico42 cities15.7
  7. 7South Korea133 cities14.5
  8. 8Senegal4 cities14.2
  9. 9Lebanon3 cities14.0
  10. 10New Zealand6 cities13.2
  11. 11Kazakhstan4 cities13.0
  12. 12Brazil6 cities12.6
  13. 13Thailand78 cities11.9
  14. 14Taiwan44 cities10.5
  15. 15Malta5 cities10.4
  16. 16Serbia8 cities9.9
  17. 17Italy30 cities, was 98.7
  18. 18Greece9 cities8.6
  19. 19North Macedonia10 cities8.5
  20. 20Japan571 cities8.3

+ 24 more countries, 7.7 µg/m³ and below

  1. 27United States855 cities6.0

Not counted on this day, too few cities measured: Laos since 10 Jun 2026, Martinique since 8 Jun 2026, Hong Kong since 7 Jun 2026 and 5 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.