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 24 May 2023: Pakistan 38.1 µg/m³, Chile 32.5 µg/m³ and India 29.3 µg/m³.
- 1Pakistan4 cities38.1
- 2Chile45 cities32.5
- 3India5 cities29.3
- 4Thailand9 cities, was 7725.9
- 5Mexico13 cities, was 4721.0
- 6Serbia3 cities, was 2114.9
- 7Luxembourg3 cities13.0
- 8Czechia34 cities12.9
- 9Belgium41 cities12.1
- 10Greece7 cities11.9
- 11Slovakia26 cities11.2
- 12Poland56 cities10.8
- 13Singapore5 cities10.7
- 14Austria30 cities10.5
- 15Germany194 cities10.5
- 16United States741 cities10.4
- 17France129 cities10.2
- 18Malta3 cities10.1
- 19Romania6 cities10.1
- 20Ireland4 cities9.8
+ 12 more countries, 9.7 µg/m³ and below
Not counted on this day, too few cities measured: Australia since 24 May 2023, Hong Kong since 24 May 2023, The Netherlands since 24 May 2023 and 8 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.