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 to25 May 2024 That day's board

The worst cities for PM2.5 over the 7 days to 25 May 2024: N'Djamena 164.4 µg/m³, Coyhaique 140.5 µg/m³ and Santa María 118.4 µg/m³.

  1. 1N'DjamenaChad164.4
  2. 2CoyhaiqueChile140.5
  3. 3Santa MaríaPeru118.4
  4. 4NacimientoChile108.4
  5. 5San CarlosChile102.0
  6. 6HualpénChile98.5
  7. 7CuranilahueChile83.3
  8. 8ChillánChile80.7
  9. 9DhakaBangladesh80.2
  10. 10LajaChile80.2
  11. 11LahorePakistan78.7
  12. 12OsornoChile73.8
  13. 13CairoEgypt67.8
  14. 14CoronelChile66.3
  15. 15Santa Anita - Los FicusPeru66.3
  16. 16DelhiIndia66.1
  17. 17Puerto VarasChile64.3
  18. 18La UniónChile63.9
  19. 19Puerto AysénChile63.4
  20. 20Los ÁngelesChile63.3

+ 2,798 more cities, the next at 62.5 µg/m³

Not counted on this day, too few days measured: Cataño since 24 May 2024, Rengo since 23 May 2024, Jakarta since 21 May 2024 and 2 more cities.

30 days7 days
GoodModerateUnhealthy for sensitive 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, Turkey and Iran, which publish only on their own websites. We are building the reader for China's network. The networks of Turkey and Iran don't answer requests from outside their countries, so we can't read them. Most cities there are missing from this board, not clean. Why.