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 5 Feb 2026: Pakistan 171.4 µg/m³, Kyrgyzstan 158.7 µg/m³ and Kazakhstan 91.0 µg/m³.
- 1Pakistan11 cities171.4
- 2Kyrgyzstan3 cities158.7
- 3Kazakhstan4 cities91.0
- 4North Macedonia13 cities43.5
- 5Ghana4 cities40.3
- 6Montenegro5 cities40.2
- 7Poland59 cities38.1
- 8Thailand75 cities34.2
- 9Romania28 cities29.5
- 10Hungary13 cities28.8
- 11Hong Kong13 cities25.6
- 12Bulgaria4 cities22.5
- 13Laos3 cities22.4
- 14Slovenia12 cities22.3
- 15Austria42 cities22.1
- 16Latvia4 cities21.9
- 17Philippines3 cities21.6
- 18Germany253 cities20.7
- 19The Netherlands37 cities20.4
- 20South Korea140 cities20.0
+ 25 more countries, 19.0 µg/m³ and below
- 36United States884 cities7.4
Not counted on this day, too few cities measured: Bosnia and Herzegovina since 29 Jan 2026, India since 20 Jan 2026, Senegal since 17 Jan 2026 and 2 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.