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 18 Jun 2023: Chile 46.5 µg/m³, Pakistan 40.7 µg/m³ and India 26.1 µg/m³.
- 1Chile44 cities46.5
- 2Pakistan4 cities40.7
- 3India5 cities26.1
- 4China3 cities24.7
- 5Mexico10 cities18.5
- 6United Kingdom4 cities13.8
- 7Belgium41 cities12.3
- 8Luxembourg3 cities12.1
- 9Lithuania4 cities12.0
- 10Canada104 cities11.3
- 11Ireland4 cities11.2
- 12Malta4 cities11.2
- 13Thailand11 cities11.1
- 14Czechia36 cities10.6
- 15Serbia3 cities10.5
- 16Germany193 cities10.4
- 17Greece8 cities10.3
- 18France129 cities10.0
- 19Switzerland9 cities9.8
- 20Italy29 cities9.6
+ 11 more countries, 9.6 µg/m³ and below
- 21United States746 cities9.6
Not counted on this day, too few cities measured: Hong Kong since 15 Jun 2023, Martinique since 15 Jun 2023, The Netherlands since 15 Jun 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.