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 4 Mar 2023: Poland 28.2 µg/m³, North Macedonia 27.3 µg/m³ and Bosnia and Herzegovina 25.2 µg/m³.
- 1Poland70 cities28.2
- 2North Macedonia11 cities27.3
- 3Bosnia and Herzegovina4 cities25.2
- 4Czechia36 cities23.3
- 5Romania7 cities23.1
- 6Slovenia8 cities20.3
- 7Slovakia33 cities20.1
- 8Kosovo6 cities19.4
- 9France129 cities19.1
- 10Greece10 cities18.9
- 11Austria17 cities16.9
- 12Germany173 cities12.3
- 13Belgium35 cities12.2
- 14Italy36 cities, was 910.7
- 15Portugal7 cities9.4
- 16The Netherlands26 cities9.0
- 17Norway17 cities8.6
- 18Spain88 cities8.0
- 19United States424 cities7.8
- 20Latvia4 cities7.3
+ 3 more countries, 4.1 µg/m³ and below
Not counted on this day, too few cities measured: Lithuania since 4 Mar 2023, Croatia since 28 Feb 2023, Australia since 4 Feb 2023 and 21 more countries. Days missing from the source archive fall in this window, so fewer countries are counted.
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.