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 2 Sep 2026: Malawi 65.3 µg/m³, Indonesia 44.9 µg/m³ and Pakistan 35.2 µg/m³.
- 1Malawi3 cities65.3
- 2Indonesia4 cities44.9
- 3Pakistan15 cities35.2
- 4India4 cities, was 21227.6
- 5Chile46 cities23.5
- 6Lebanon3 cities22.6
- 7South Africa45 cities19.8
- 8Nepal3 cities19.4
- 9Montenegro4 cities18.5
- 10Ghana3 cities18.2
- 11Mexico48 cities15.4
- 12North Macedonia15 cities15.1
- 13Greece8 cities14.3
- 14Serbia8 cities14.2
- 15Kazakhstan5 cities12.7
- 16Italy32 cities12.4
- 17Hong Kong12 cities10.7
- 18Thailand75 cities10.7
- 19Romania26 cities10.3
- 20Brazil6 cities9.0
+ 29 more countries, 8.5 µg/m³ and below
- 28United States901 cities7.4
Not counted on this day, too few cities measured: Kyrgyzstan since 2 Sep 2026, Martinique since 2 Sep 2026, Bosnia and Herzegovina since 12 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.