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 to22 May 2025 That day's board

The worst cities for PM2.5 over the 7 days to 22 May 2025: Aya Nagar 88.9 µg/m³, Hualpén 87.4 µg/m³ and Muzaffarnagar 83.4 µg/m³.

  1. 1Aya NagarIndia88.9
  2. 2HualpénChile87.4
  3. 3MuzaffarnagarIndia83.4
  4. 4DushanbeTajikistan81.5
  5. 5NacimientoChile79.5
  6. 6Santa Anita - Los FicusPeru75.1
  7. 7NarelaIndia74.7
  8. 8OsornoChile74.3
  9. 9BawānaIndia73.2
  10. 10GobindgarhIndia72.4
  11. 11LudhianaIndia70.7
  12. 12CuddaloreIndia69.3
  13. 13LoniIndia64.5
  14. 14CoyhaiqueChile64.5
  15. 15PatiālaIndia64.2
  16. 16KhannaIndia63.5
  17. 17BathindaIndia63.3
  18. 18SasarāmIndia62.3
  19. 19LucknowIndia62.3
  20. 20Dera MāndiIndia62.1

+ 2,882 more cities, 62.0 µg/m³ and below

Not counted on this day, too few days measured: Nagapattinam since 22 May 2025, Bāghpat since 22 May 2025, Ramanathapuram since 20 May 2025 and 10 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.