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 27 Feb 2023: North Macedonia 37.3 µg/m³, Slovenia 28.9 µg/m³ and Greece 22.5 µg/m³.
- 1North Macedonia11 cities37.3
- 2Slovenia8 cities28.9
- 3Greece10 cities22.5
- 4Bosnia and Herzegovina4 cities21.6
- 5Italy36 cities, was 921.1
- 6Kosovo6 cities20.0
- 7Croatia3 cities16.8
- 8Romania7 cities16.7
- 9Latvia4 cities13.8
- 10Poland69 cities13.7
- 11Belgium35 cities12.8
- 12France127 cities12.7
- 13Spain88 cities12.3
- 14Slovakia33 cities11.7
- 15The Netherlands27 cities11.6
- 16Czechia36 cities10.5
- 17Austria17 cities10.2
- 18Germany172 cities9.9
- 19Portugal8 cities8.9
- 20Finland13 cities8.1
+ 5 more countries, 8.0 µg/m³ and below
- 22United States423 cities7.2
Not counted on this day, too few cities measured: Australia since 4 Feb 2023, Bulgaria since 4 Feb 2023, Brazil since 4 Feb 2023 and 19 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.