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 30 days to 14 Jul 2026: Chile 51.5 µg/m³, Pakistan 32.1 µg/m³ and Malawi 29.5 µg/m³.
- 1Chile46 cities51.5
- 2Pakistan15 cities32.1
- 3Malawi5 cities29.5
- 4Peru6 cities26.1
- 5India205 cities23.9
- 6Lebanon3 cities18.2
- 7New Zealand6 cities14.4
- 8Kazakhstan4 cities13.1
- 9Mexico44 cities13.0
- 10Martinique3 cities12.4
- 11Brazil26 cities11.9
- 12Italy32 cities11.7
- 13Slovakia39 cities11.7
- 14Malta5 cities11.1
- 15South Korea131 cities11.0
- 16Bosnia and Herzegovina4 cities10.9
- 17Serbia8 cities10.9
- 18Montenegro4 cities9.3
- 19Senegal4 cities9.3
- 20Romania25 cities9.1
+ 24 more countries, the next at 9.0 µg/m³
- 30United States863 cities7.6
Not counted on this day, too few cities measured: Thailand since 11 Jul 2026, Norway since 6 Jul 2026, Greece since 14 Jun 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 reader for China's network. Turkey's network doesn't answer requests from outside the country, so we can't read it. Most cities there are missing from this board, not clean. Why.