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 6 Oct 2025: Pakistan 63.7 µg/m³, Peru 26.7 µg/m³ and Philippines 24.5 µg/m³.
- 1Pakistan11 cities63.7
- 2Peru5 cities26.7
- 3Philippines3 cities24.5
- 4India212 cities22.6
- 5Chile44 cities21.1
- 6Serbia33 cities17.0
- 7Ghana4 cities16.0
- 8Taiwan45 cities13.6
- 9Poland73 cities13.4
- 10Mexico52 cities12.8
- 11Thailand74 cities11.7
- 12South Korea141 cities10.7
- 13Lithuania3 cities10.5
- 14Hungary4 cities, was 1210.4
- 15Brazil3 cities9.2
- 16The Netherlands23 cities8.4
- 17Germany11 cities, was 2518.3
- 18North Macedonia8 cities8.2
- 19Spain55 cities8.1
- 20Hong Kong13 cities7.7
+ 15 more countries, 7.5 µg/m³ and below
- 25United States859 cities6.4
Not counted on this day, too few cities measured: Bosnia and Herzegovina since 6 Oct 2025, Switzerland since 6 Oct 2025, Finland since 6 Oct 2025 and 13 more countries.
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.