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 worst cities for PM2.5 over the 30 days to 27 Nov 2023: Lahore 257.7 µg/m³, Delhi 232.6 µg/m³ and Kolkata 124.2 µg/m³.
- 1LahorePakistan257.7
- 2DelhiIndia232.6
- 3KolkataIndia124.2
- 4N'DjamenaChad120.5
- 5DhakaBangladesh108.5
- 6KarachiPakistan98.0
- 7IslamabadPakistan76.8
- 8HyderabadIndia76.5
- 9MumbaiIndia73.8
- 10Ulan BatorMongolia65.9
- 11CairoEgypt53.0
- 12BeijingChina50.0
- 13MoreliaMexico45.6
- 14JakartaIndonesia45.5
- 15SarajevoBosnia and Herzegovina45.3
- 16AbujaNigeria44.8
- 17Şabāḩ as SālimKuwait44.5
- 18Samut SakhonThailand39.9
- 19ShenyangChina39.2
- 20Tha BoThailand35.7
+ 2,341 more cities, the next at 35.7 µg/m³
Not counted on this day, too few days measured: Ashgabat since 26 Nov 2023, Peshawar since 25 Nov 2023, Salor since 25 Nov 2023 and 11 more cities.
Cities counted each 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.