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 16 Nov 2025: Pakistan 183.9 µg/m³, India 62.8 µg/m³ and Bosnia and Herzegovina 43.8 µg/m³.
- 1Pakistan11 cities183.9
- 2India226 cities62.8
- 3Bosnia and Herzegovina5 cities43.8
- 4North Macedonia13 cities34.1
- 5Peru5 cities32.3
- 6Ghana4 cities22.7
- 7Montenegro5 cities20.4
- 8Mexico44 cities19.9
- 9Kosovo8 cities19.5
- 10Slovenia12 cities19.3
- 11Hungary13 cities18.5
- 12Poland67 cities18.0
- 13Chile43 cities17.2
- 14South Korea140 cities16.9
- 15Bulgaria7 cities16.6
- 16Slovakia41 cities15.5
- 17Romania7 cities15.0
- 18Czechia17 cities14.8
- 19Hong Kong13 cities13.8
- 20Austria37 cities12.4
+ 24 more countries, the next at 10.8 µg/m³
- 37United States268 cities, was 8695.7
Not counted on this day, too few cities measured: Philippines since 14 Nov 2025, Lithuania since 29 Oct 2025, Italy since 28 Oct 2025 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, Turkey and Iran, which publish only on their own websites. We are building the reader for China's network. The networks of Turkey and Iran don't answer requests from outside their countries, so we can't read them. Most cities there are missing from this board, not clean. Why.