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 10 Jan 2026: Pakistan 151.9 µg/m³, Montenegro 119.9 µg/m³ and Kazakhstan 88.4 µg/m³.
- 1Pakistan13 cities151.9
- 2Montenegro3 cities119.9
- 3Kazakhstan4 cities88.4
- 4India241 cities62.3
- 5Poland56 cities30.9
- 6North Macedonia9 cities28.3
- 7Hungary13 cities27.1
- 8Mexico44 cities25.7
- 9Malta4 cities24.6
- 10Thailand74 cities24.5
- 11Slovenia12 cities21.9
- 12Hong Kong13 cities21.8
- 13Austria42 cities19.6
- 14Romania19 cities19.5
- 15Peru6 cities18.9
- 16Taiwan45 cities18.5
- 17South Korea139 cities17.4
- 18Chile46 cities17.2
- 19Laos3 cities15.3
- 20Latvia3 cities12.6
+ 15 more countries, 12.5 µg/m³ and below
- 26United States862 cities, was 2658.1
Not counted on this day, too few cities measured: Belgium since 10 Jan 2026, Senegal since 10 Jan 2026, Bosnia and Herzegovina since 9 Jan 2026 and 14 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.