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 22 Aug 2026: Malawi 38.5 µg/m³, Chile 35.6 µg/m³ and South Africa 28.9 µg/m³.
- 1Malawi5 cities38.5
- 2Chile45 cities35.6
- 3South Africa43 cities28.9
- 4Lebanon3 cities28.6
- 5Pakistan14 cities28.3
- 6Nepal3 cities27.1
- 7India233 cities22.4
- 8North Macedonia15 cities15.3
- 9Luxembourg3 cities15.1
- 10Mexico49 cities14.8
- 11Montenegro4 cities14.5
- 12Greece4 cities12.8
- 13Serbia8 cities12.2
- 14Brazil6 cities10.8
- 15South Korea124 cities10.6
- 16Romania26 cities, was 710.5
- 17Thailand75 cities10.3
- 18Italy26 cities10.1
- 19Senegal4 cities9.9
- 20Hungary11 cities, was 49.5
+ 26 more countries, 9.3 µg/m³ and below
- 26United States855 cities7.3
Not counted on this day, too few cities measured: Indonesia since 22 Aug 2026, Latvia since 17 Aug 2026, Bosnia and Herzegovina since 12 Aug 2026 and 7 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.