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 9 Mar 2026: Pakistan 80.2 µg/m³, Kyrgyzstan 67.4 µg/m³ and Kazakhstan 56.8 µg/m³.
- 1Pakistan15 cities80.2
- 2Kyrgyzstan3 cities67.4
- 3Kazakhstan4 cities56.8
- 4India233 cities, was 23949.6
- 5Laos3 cities37.7
- 6Poland60 cities35.1
- 7North Macedonia15 cities34.4
- 8Montenegro5 cities33.9
- 9Hungary12 cities30.1
- 10Thailand84 cities29.0
- 11Ghana4 cities27.7
- 12Romania28 cities27.7
- 13Switzerland10 cities26.4
- 14Bosnia and Herzegovina6 cities26.2
- 15The Netherlands37 cities25.8
- 16Belgium51 cities24.8
- 17Mexico51 cities22.5
- 18Slovenia12 cities21.8
- 19Latvia4 cities19.5
- 20Germany251 cities19.4
+ 28 more countries, 18.9 µg/m³ and below
- 38United States873 cities7.0
Not counted on this day, too few cities measured: Czechia since 25 Feb 2026, Spain since 11 Feb 2026 and Martinique since 30 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.