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 4 Oct 2026: Pakistan 45.6 µg/m³, India 44.8 µg/m³ and Indonesia 38.1 µg/m³.
- 1Pakistan15 cities45.6
- 2India3 cities44.8
- 3Indonesia4 cities38.1
- 4Philippines3 cities33.5
- 5Malawi4 cities30.8
- 6Nigeria3 cities26.0
- 7Ghana4 cities19.9
- 8Chile45 cities19.8
- 9Serbia8 cities18.0
- 10Thailand71 cities14.0
- 11Italy18 cities13.9
- 12Kazakhstan5 cities13.2
- 13Taiwan44 cities13.0
- 14Slovakia38 cities11.7
- 15Hungary10 cities11.6
- 16Bosnia and Herzegovina5 cities11.3
- 17South Africa35 cities11.3
- 18Austria39 cities10.9
- 19Slovenia12 cities10.6
- 20Malta5 cities10.5
+ 31 more countries, 10.3 µg/m³ and below
- 44United States878 cities5.8
Not counted on this day, too few cities measured: Martinique since 4 Oct 2026, Poland since 3 Oct 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.