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 7 Feb 2023: North Macedonia 26.9 µg/m³, Slovenia 25.2 µg/m³ and Bosnia and Herzegovina 21.1 µg/m³.
- 1North Macedonia11 cities26.9
- 2Slovenia8 cities25.2
- 3Bosnia and Herzegovina4 cities21.1
- 4Poland69 cities18.8
- 5Romania7 cities15.7
- 6Czechia36 cities14.7
- 7Portugal6 cities14.4
- 8Greece10 cities13.3
- 9Italy33 cities12.7
- 10Slovakia33 cities11.9
- 11Belgium34 cities11.7
- 12Spain91 cities11.0
- 13Norway17 cities10.6
- 14France128 cities9.6
- 15Austria16 cities9.4
- 16Germany171 cities9.4
- 17The Netherlands26 cities9.1
- 18Latvia4 cities9.0
- 19United States416 cities8.1
- 20Reunion3 cities5.6
+ 2 more countries, 4.2 µg/m³ and below
Not counted on this day, too few cities measured: Kosovo since 5 Feb 2023, Australia since 4 Feb 2023, Bulgaria since 4 Feb 2023 and 20 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.