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 26 Dec 2023: Pakistan 147.3 µg/m³, India 129.1 µg/m³ and North Macedonia 71.4 µg/m³.
- 1Pakistan4 cities147.3
- 2India5 cities129.1
- 3North Macedonia7 cities71.4
- 4Serbia3 cities46.7
- 5Thailand8 cities31.2
- 6China3 cities29.3
- 7Mexico45 cities, was 1124.5
- 8Greece10 cities22.7
- 9Italy24 cities, was 2820.9
- 10Romania8 cities20.6
- 11Hong Kong13 cities19.5
- 12Chile45 cities18.3
- 13Bulgaria5 cities17.6
- 14Hungary9 cities11.8
- 15Portugal18 cities9.5
- 16Slovakia27 cities9.5
- 17Spain107 cities9.4
- 18Malta4 cities8.3
- 19United States771 cities8.3
- 20Singapore5 cities7.1
+ 16 more countries, 6.5 µg/m³ and below
Not counted on this day, too few cities measured: Luxembourg since 5 Dec 2023 and Martinique since 1 Dec 2023.
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.