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 30 days to 25 Feb 2023: North Macedonia 43.6 µg/m³, Slovenia 35.7 µg/m³ and Bosnia and Herzegovina 29.3 µg/m³.
- 1North Macedonia11 cities43.6
- 2Slovenia8 cities35.7
- 3Bosnia and Herzegovina4 cities29.3
- 4Romania7 cities26.0
- 5Slovakia33 cities20.0
- 6Poland69 cities19.9
- 7Italy31 cities19.6
- 8Greece10 cities18.8
- 9Czechia36 cities17.9
- 10Belgium34 cities17.7
- 11France124 cities16.9
- 12Austria16 cities13.7
- 13The Netherlands25 cities13.7
- 14Germany168 cities13.6
- 15Spain87 cities12.6
- 16Latvia4 cities10.4
- 17Portugal8 cities9.6
- 18Norway17 cities9.2
- 19United States419 cities7.4
- 20Finland13 cities5.6
+ 2 more countries, 4.8 µg/m³ and below
Not counted on this day, too few cities measured: Bulgaria since 6 Feb 2023, United Kingdom since 6 Feb 2023, Brazil since 5 Feb 2023 and 12 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.