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 7 days to 26 Mar 2024: N'Djamena 149.6 µg/m³, Delhi 101.3 µg/m³ and Lahore 91.7 µg/m³.
- 1N'DjamenaChad149.6
- 2DelhiIndia101.3
- 3LahorePakistan91.7
- 4DhakaBangladesh89.7
- 5KathmanduNepal76.7
- 6BeijingChina63.4
- 7PeshawarPakistan61.7
- 8Mae SaiThailand60.6
- 9MukdahanThailand59.2
- 10Mae SotThailand58.3
- 11KampalaUganda57.9
- 12LamphunThailand57.9
- 13Ubon RatchathaniThailand56.1
- 14LampangThailand55.9
- 15Chiang MaiThailand55.6
- 16KalasinThailand54.7
- 17YasothonThailand53.7
- 18NanThailand51.1
- 19PhayaoThailand50.9
- 20KolkataIndia50.9
+ 1,732 more cities, the next at 48.2 µg/m³
Not counted on this day, too few days measured: Dębica since 24 Mar 2024, Wan Chai since 22 Mar 2024, Mong Kok since 22 Mar 2024 and 9 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.