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 16 Mar 2026: Pakistan 96.8 µg/m³, Kyrgyzstan 73.7 µg/m³ and Kazakhstan 53.6 µg/m³.
- 1Pakistan13 cities96.8
- 2Kyrgyzstan3 cities73.7
- 3Kazakhstan4 cities53.6
- 4India219 cities47.0
- 5Laos3 cities32.8
- 6Thailand85 cities28.0
- 7Ghana4 cities27.8
- 8North Macedonia13 cities27.8
- 9Poland59 cities25.5
- 10Montenegro5 cities24.0
- 11Latvia4 cities23.4
- 12Romania28 cities22.6
- 13Bosnia and Herzegovina6 cities22.1
- 14Hungary13 cities21.3
- 15Senegal3 cities19.9
- 16Mexico48 cities19.8
- 17South Korea141 cities19.5
- 18Hong Kong13 cities19.4
- 19Philippines3 cities18.7
- 20Peru6 cities17.8
+ 28 more countries, the next at 17.5 µg/m³
- 43United States879 cities6.7
Not counted on this day, too few cities measured: Spain since 18 Feb 2026.
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.