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 3 Feb 2026: Pakistan 140.7 µg/m³, Kyrgyzstan 107.2 µg/m³ and Kazakhstan 96.3 µg/m³.
- 1Pakistan11 cities140.7
- 2Kyrgyzstan3 cities107.2
- 3Kazakhstan4 cities96.3
- 4India227 cities55.5
- 5Ghana4 cities41.8
- 6Thailand77 cities34.7
- 7North Macedonia13 cities32.9
- 8Laos3 cities28.3
- 9Poland57 cities27.7
- 10Montenegro5 cities25.5
- 11Bosnia and Herzegovina6 cities25.2
- 12The Netherlands37 cities21.9
- 13Austria42 cities21.7
- 14Hong Kong12 cities21.7
- 15Romania29 cities20.1
- 16Germany251 cities18.8
- 17Latvia4 cities18.5
- 18Mexico39 cities18.5
- 19South Korea140 cities18.3
- 20Hungary13 cities17.9
+ 28 more countries, 17.8 µg/m³ and below
- 36United States879 cities8.0
Not counted on this day, too few cities measured: Czechia since 30 Jan 2026, Martinique since 30 Jan 2026, Senegal since 10 Jan 2026 and Slovakia since 3 Jan 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 readers for them. Most cities there are missing from this board, not clean. Why.