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 13 Jun 2024: Coyhaique 154.0 µg/m³, N'Djamena 119.7 µg/m³ and Santa María 112.9 µg/m³.
- 1CoyhaiqueChile154.0
- 2N'DjamenaChad119.7
- 3Santa MaríaPeru112.9
- 4OsornoChile97.0
- 5NacimientoChile90.4
- 6HualpénChile76.1
- 7Puerto VarasChile70.7
- 8DelhiIndia70.2
- 9CuranilahueChile68.3
- 10San CarlosChile68.0
- 11CuricóChile63.7
- 12La UniónChile63.3
- 13RengoChile62.3
- 14DhakaBangladesh61.8
- 15Santa Anita - Los FicusPeru61.1
- 16ChillánChile59.6
- 17Los ÁngelesChile56.6
- 18RancaguaChile56.0
- 19Puerto AysénChile55.4
- 20VillarricaChile54.2
+ 2,623 more cities, 53.3 µg/m³ and below
Not counted on this day, too few days measured: Laja since 13 Jun 2024, Lahore since 7 Jun 2024 and Tlaquepaque since 23 May 2024.
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 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.