SmogRank / History / Country race
Countries, worst air first, day by day
Each country's typical measured city over the 30 days to every day since January 2023, worst first. Press Play to watch the order change, or drag the slider to any day.
The worst countries for PM2.5 over the 7 days to 22 Feb 2024: India 89.2 µg/m³, Pakistan 64.3 µg/m³ and Serbia 43.2 µg/m³.
- 1India5 cities89.2
- 2Pakistan3 cities64.3
- 3Serbia24 cities43.2
- 4Italy31 cities42.0
- 5North Macedonia9 cities41.0
- 6Montenegro3 cities32.2
- 7Thailand78 cities28.5
- 8Bulgaria6 cities23.2
- 9Romania10 cities21.6
- 10Greece8 cities19.3
- 11Peru6 cities18.9
- 12Chile43 cities18.1
- 13Mexico14 cities15.4
- 14Slovakia42 cities15.3
- 15Hungary10 cities15.1
- 16Poland78 cities15.0
- 17South Africa22 cities13.7
- 18Hong Kong13 cities12.8
- 19Singapore5 cities12.2
- 20Czechia38 cities11.2
+ 20 more countries, 10.7 µg/m³ and below
- 32United States781 cities6.6
Not counted on this day, too few cities measured: China since 18 Feb 2024, Germany since 18 Feb 2024, Croatia since 18 Feb 2024 and 2 more countries.
Countries counted each day
A country's number is its typical measured city: the median of its cities' means over the 30 days (a city needs 21 of them measured; 5 of 7 on the 7-day race), shown only with 3 such cities. A country whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air; "was" beside a city count marks a month after many cities joined or left. 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.