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 9 Mar 2023: Bosnia and Herzegovina 27.7 µg/m³, North Macedonia 27.5 µg/m³ and Slovenia 27.5 µg/m³.
- 1Bosnia and Herzegovina4 cities27.7
- 2North Macedonia11 cities27.5
- 3Slovenia8 cities27.5
- 4Romania8 cities24.2
- 5Slovakia33 cities19.0
- 6Poland70 cities18.8
- 7France127 cities18.7
- 8Austria17 cities16.6
- 9Kosovo6 cities16.4
- 10Croatia3 cities15.7
- 11Czechia36 cities15.5
- 12Greece10 cities13.1
- 13Belgium35 cities12.0
- 14Germany173 cities11.0
- 15Italy36 cities, was 910.7
- 16Portugal8 cities10.5
- 17Spain88 cities8.6
- 18Latvia4 cities7.1
- 19The Netherlands27 cities6.7
- 20United States420 cities6.7
+ 3 more countries, 6.6 µg/m³ and below
Not counted on this day, too few cities measured: Reunion since 6 Mar 2023, Lithuania since 4 Mar 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.