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 19 May 2024: Chile 58.1 µg/m³, Pakistan 38.7 µg/m³ and China 29.2 µg/m³.
- 1Chile44 cities58.1
- 2Pakistan4 cities38.7
- 3China3 cities29.2
- 4Malta5 cities26.9
- 5India5 cities24.3
- 6Laos3 cities23.6
- 7Mexico12 cities22.7
- 8Peru12 cities21.3
- 9Thailand79 cities20.3
- 10Taiwan43 cities15.8
- 11New Zealand5 cities15.3
- 12Hong Kong13 cities15.0
- 13Greece7 cities13.1
- 14The Netherlands36 cities12.7
- 15South Korea141 cities12.2
- 16Belgium44 cities11.4
- 17Singapore5 cities11.2
- 18Latvia4 cities10.9
- 19Serbia24 cities10.5
- 20United Kingdom62 cities, was 1110.0
+ 28 more countries, 9.8 µg/m³ and below
- 39United States794 cities6.2
Not counted on this day, too few cities measured: Luxembourg since 19 May 2024, Austria since 10 May 2024, Bosnia and Herzegovina since 26 Apr 2024 and Montenegro since 22 Mar 2024.
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.