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 5 Oct 2026: Pakistan 48.3 µg/m³, India 36.9 µg/m³ and Indonesia 34.3 µg/m³.
- 1Pakistan15 cities48.3
- 2India169 cities36.9
- 3Indonesia4 cities34.3
- 4Philippines3 cities32.9
- 5Nigeria3 cities28.7
- 6Malawi4 cities28.3
- 7Ghana4 cities20.8
- 8Chile45 cities20.0
- 9Serbia8 cities18.7
- 10Kazakhstan4 cities17.9
- 11Thailand72 cities15.0
- 12Italy15 cities14.6
- 13Taiwan44 cities13.2
- 14Slovakia37 cities12.4
- 15Hungary10 cities12.2
- 16Bosnia and Herzegovina5 cities11.6
- 17Austria39 cities11.1
- 18Switzerland10 cities, was 1110.7
- 19Malta5 cities10.7
- 20Slovenia12 cities10.4
+ 30 more countries, 10.3 µg/m³ and below
- 45United States871 cities5.8
Not counted on this day, too few cities measured: Iceland since 5 Oct 2026, Martinique since 4 Oct 2026, Poland since 3 Oct 2026 and 3 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.