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 Jan 2026: Pakistan 193.8 µg/m³, Kazakhstan 85.6 µg/m³ and India 64.6 µg/m³.
- 1Pakistan12 cities193.8
- 2Kazakhstan4 cities85.6
- 3India223 cities64.6
- 4Bosnia and Herzegovina5 cities63.5
- 5Montenegro4 cities60.3
- 6North Macedonia13 cities51.3
- 7Ghana3 cities35.4
- 8Thailand75 cities27.0
- 9Peru6 cities25.4
- 10Hong Kong13 cities24.5
- 11Poland59 cities24.4
- 12Romania24 cities22.8
- 13Mexico46 cities22.0
- 14Hungary13 cities20.3
- 15Slovenia12 cities19.6
- 16Laos3 cities19.1
- 17South Korea140 cities17.3
- 18Chile43 cities17.2
- 19Bulgaria7 cities16.9
- 20Austria38 cities15.3
+ 24 more countries, 15.3 µg/m³ and below
- 36United States868 cities7.3
Not counted on this day, too few cities measured: Slovakia since 9 Jan 2026, Czechia since 7 Jan 2026, Philippines since 4 Jan 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.