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 3 Oct 2026: Pakistan 47.0 µg/m³, Indonesia 42.2 µg/m³ and India 33.1 µg/m³.
- 1Pakistan15 cities47.0
- 2Indonesia4 cities42.2
- 3India200 cities33.1
- 4Philippines3 cities32.9
- 5Malawi4 cities32.3
- 6Chile45 cities19.6
- 7Ghana4 cities19.3
- 8Serbia8 cities17.6
- 9Kazakhstan4 cities17.1
- 10Italy21 cities13.4
- 11Taiwan44 cities13.1
- 12Thailand71 cities12.9
- 13Hungary11 cities11.8
- 14Bosnia and Herzegovina5 cities11.3
- 15South Africa35 cities11.0
- 16Austria39 cities10.9
- 17Slovakia40 cities10.7
- 18Switzerland10 cities, was 1110.4
- 19South Korea138 cities10.3
- 20Slovenia12 cities10.3
+ 31 more countries, 9.9 µg/m³ and below
- 43United States897 cities5.8
Not counted on this day, too few cities measured: Poland since 3 Oct 2026, Nigeria since 20 Sep 2026, Nepal since 14 Sep 2026 and 2 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.