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 7 Aug 2026: Malawi 43.1 µg/m³, Pakistan 34.9 µg/m³ and Chile 27.4 µg/m³.
- 1Malawi5 cities43.1
- 2Pakistan14 cities34.9
- 3Chile47 cities27.4
- 4Nepal3 cities23.8
- 5Lebanon3 cities21.9
- 6India195 cities21.1
- 7New Zealand6 cities16.4
- 8Slovakia39 cities16.4
- 9Brazil6 cities16.3
- 10Mexico48 cities15.8
- 11Italy29 cities14.9
- 12Kazakhstan4 cities14.3
- 13South Korea132 cities13.8
- 14Bosnia and Herzegovina5 cities13.2
- 15Romania19 cities, was 712.9
- 16Hungary10 cities, was 412.6
- 17Poland59 cities, was 1412.3
- 18Serbia8 cities12.1
- 19Slovenia12 cities10.8
- 20Montenegro4 cities10.4
+ 27 more countries, 10.4 µg/m³ and below
- 27United States858 cities9.0
Not counted on this day, too few cities measured: Lithuania since 7 Aug 2026, Malta since 7 Aug 2026, Luxembourg since 6 Aug 2026 and 4 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.