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 13 Aug 2026: Malawi 50.4 µg/m³, Chile 37.0 µg/m³ and Pakistan 36.1 µg/m³.
- 1Malawi5 cities50.4
- 2Chile46 cities37.0
- 3Pakistan14 cities36.1
- 4Lebanon3 cities26.1
- 5Nepal3 cities21.9
- 6India221 cities21.1
- 7Hong Kong12 cities18.9
- 8Mexico37 cities15.3
- 9Italy33 cities15.0
- 10Taiwan42 cities13.7
- 11North Macedonia14 cities13.1
- 12Serbia8 cities13.1
- 13Kazakhstan4 cities13.0
- 14Montenegro4 cities13.0
- 15New Zealand6 cities12.3
- 16Brazil25 cities11.7
- 17Spain73 cities11.4
- 18Greece12 cities11.4
- 19Romania28 cities, was 710.6
- 20Slovakia40 cities10.3
+ 26 more countries, the next at 9.1 µg/m³
- 22United States861 cities8.7
Not counted on this day, too few cities measured: Bosnia and Herzegovina since 12 Aug 2026, Lithuania since 12 Aug 2026, Martinique since 12 Aug 2026 and 5 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 reader for China's network. Turkey's network doesn't answer requests from outside the country, so we can't read it. Most cities there are missing from this board, not clean. Why.