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 11 Jan 2026: Pakistan 154.1 µg/m³, Kazakhstan 103.0 µg/m³ and India 62.5 µg/m³.
- 1Pakistan13 cities154.1
- 2Kazakhstan4 cities103.0
- 3India227 cities62.5
- 4Poland56 cities30.8
- 5North Macedonia8 cities29.4
- 6Hungary13 cities28.7
- 7Thailand77 cities25.9
- 8Mexico40 cities24.3
- 9Slovenia12 cities22.0
- 10Malta3 cities21.6
- 11Romania19 cities21.5
- 12Hong Kong13 cities21.2
- 13Austria42 cities19.7
- 14Taiwan45 cities19.6
- 15Peru6 cities18.7
- 16Chile45 cities17.1
- 17Laos3 cities15.5
- 18South Korea139 cities14.4
- 19Latvia3 cities11.8
- 20Switzerland9 cities11.4
+ 14 more countries, 11.3 µg/m³ and below
- 26United States862 cities, was 2657.6
Not counted on this day, too few cities measured: Montenegro since 11 Jan 2026, Belgium since 10 Jan 2026, Senegal since 10 Jan 2026 and 15 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.