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.

CountriesCities
The 7 days to11 Sep 2025 That day's board

The worst cities for PM2.5 over the 7 days to 11 Sep 2025: Mothīhāri 91.6 µg/m³, Gummidipundi 79.2 µg/m³ and Mammoth Lakes 73.0 µg/m³.

  1. 1MothīhāriIndia91.6
  2. 2GummidipundiIndia79.2
  3. 3Mammoth LakesUnited States73.0
  4. 4ChāpraIndia71.6
  5. 5AurangābādIndia70.5
  6. 6FaisalabadPakistan69.4
  7. 7CoyhaiqueChile63.4
  8. 8RourkelaIndia60.6
  9. 9NacimientoChile59.8
  10. 10RasapūdipalemIndia59.7
  11. 11Bihār SharīfIndia57.3
  12. 12IstanbulTurkey56.3
  13. 13DushanbeTajikistan56.0
  14. 14KanchipuramIndia55.8
  15. 15GujranwalaPakistan55.1
  16. 16KigaliRwanda54.9
  17. 17OsornoChile52.0
  18. 18OotyIndia51.2
  19. 19CuddaloreIndia50.9
  20. 20Puerto VarasChile50.3

+ 3,117 more cities, 49.5 µg/m³ and below

Not counted on this day, too few days measured: Kahi Kuchi since 11 Sep 2025, Samāstipur since 8 Sep 2025, Harare since 7 Sep 2025 and 12 more cities.

30 days7 days
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.