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 21 Mar 2023: North Macedonia 27.4 µg/m³, Slovenia 22.3 µg/m³ and Bosnia and Herzegovina 20.7 µg/m³.
- 1North Macedonia11 cities27.4
- 2Slovenia8 cities22.3
- 3Bosnia and Herzegovina4 cities20.7
- 4Romania7 cities19.7
- 5Poland69 cities19.4
- 6Kosovo6 cities17.3
- 7Greece10 cities15.8
- 8Slovakia33 cities15.0
- 9Czechia36 cities14.0
- 10Italy36 cities, was 613.5
- 11Croatia3 cities12.7
- 12Austria17 cities12.6
- 13France127 cities12.4
- 14Belgium35 cities10.6
- 15Latvia4 cities10.6
- 16Germany173 cities9.7
- 17Spain87 cities9.0
- 18The Netherlands27 cities9.0
- 19Portugal8 cities8.6
- 20Norway17 cities7.6
+ 3 more countries, 6.8 µg/m³ and below
- 21United States426 cities6.8
Not counted on this day, too few cities measured: Reunion since 19 Mar 2023, Lithuania since 15 Mar 2023, Bulgaria since 6 Feb 2023 and 14 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.