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 4 Mar 2026: Pakistan 84.4 µg/m³, Kyrgyzstan 64.2 µg/m³ and India 44.4 µg/m³.
- 1Pakistan14 cities84.4
- 2Kyrgyzstan3 cities64.2
- 3India238 cities, was 23944.4
- 4Kazakhstan4 cities42.8
- 5Montenegro4 cities41.5
- 6North Macedonia13 cities36.2
- 7Laos3 cities31.7
- 8Bosnia and Herzegovina6 cities28.6
- 9Ghana4 cities28.4
- 10Romania28 cities27.3
- 11Poland56 cities25.2
- 12Hungary11 cities25.1
- 13Thailand85 cities24.6
- 14Slovenia12 cities20.6
- 15Latvia4 cities19.5
- 16Mexico50 cities19.4
- 17Bulgaria7 cities19.3
- 18Philippines3 cities18.1
- 19Senegal3 cities18.0
- 20Austria42 cities17.3
+ 27 more countries, 16.9 µg/m³ and below
- 35United States882 cities7.7
Not counted on this day, too few cities measured: Malawi since 27 Feb 2026, 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.