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 13 Feb 2025: India 88.4 µg/m³, Pakistan 80.4 µg/m³ and Bosnia and Herzegovina 77.3 µg/m³.
- 1India5 cities88.4
- 2Pakistan4 cities80.4
- 3Bosnia and Herzegovina3 cities77.3
- 4Slovenia12 cities49.0
- 5Serbia38 cities38.0
- 6Thailand85 cities, was 1635.7
- 7Poland75 cities34.1
- 8China4 cities33.5
- 9Czechia35 cities, was 3730.9
- 10Germany252 cities30.5
- 11The Netherlands24 cities30.1
- 12Hungary10 cities28.0
- 13Slovakia41 cities27.4
- 14Romania9 cities26.1
- 15Belgium45 cities25.7
- 16Bulgaria5 cities25.3
- 17Laos3 cities24.4
- 18Switzerland9 cities, was 1024.2
- 19Austria36 cities23.2
- 20Chile46 cities23.2
+ 26 more countries, 21.4 µg/m³ and below
- 39United States833 cities6.7
Not counted on this day, too few cities measured: Luxembourg since 21 Jan 2025 and Singapore since 9 Jan 2025.
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.