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 1 Sep 2026: Malawi 56.9 µg/m³, Indonesia 45.5 µg/m³ and Pakistan 36.3 µg/m³.
- 1Malawi3 cities56.9
- 2Indonesia4 cities45.5
- 3Pakistan14 cities36.3
- 4India4 cities, was 21229.7
- 5Lebanon3 cities24.0
- 6Chile46 cities23.2
- 7Nepal3 cities22.1
- 8Montenegro4 cities19.4
- 9South Africa46 cities19.4
- 10Ghana5 cities18.9
- 11Kyrgyzstan3 cities17.1
- 12Mexico49 cities15.9
- 13North Macedonia15 cities15.0
- 14Serbia8 cities13.5
- 15Greece9 cities12.9
- 16Italy33 cities12.2
- 17Kazakhstan5 cities12.2
- 18Hong Kong12 cities10.9
- 19Romania26 cities10.6
- 20Thailand75 cities10.5
+ 31 more countries, 9.8 µg/m³ and below
- 28United States900 cities7.6
Not counted on this day, too few cities measured: Bosnia and Herzegovina since 12 Aug 2026, Lithuania since 12 Aug 2026, Malta since 7 Aug 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.