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 26 Mar 2023: North Macedonia 24.9 µg/m³, Romania 20.8 µg/m³ and Poland 19.4 µg/m³.
- 1North Macedonia11 cities24.9
- 2Romania7 cities20.8
- 3Poland70 cities19.4
- 4Slovenia8 cities18.4
- 5Kosovo6 cities15.8
- 6Greece10 cities15.0
- 7Slovakia32 cities14.9
- 8Czechia36 cities14.0
- 9Bosnia and Herzegovina3 cities12.9
- 10Austria17 cities11.8
- 11Italy34 cities, was 611.3
- 12France124 cities10.9
- 13Latvia4 cities10.1
- 14Belgium35 cities8.8
- 15Germany173 cities8.4
- 16Portugal8 cities7.9
- 17Spain85 cities7.6
- 18Norway17 cities7.6
- 19The Netherlands26 cities7.4
- 20United States424 cities7.0
+ 2 more countries, 4.5 µg/m³ and below
Not counted on this day, too few cities measured: Croatia since 24 Mar 2023, Reunion since 19 Mar 2023, Lithuania since 15 Mar 2023 and 15 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.