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 14 Feb 2025: India 87.6 µg/m³, Pakistan 80.7 µg/m³ and Bosnia and Herzegovina 73.7 µg/m³.
- 1India5 cities87.6
- 2Pakistan4 cities80.7
- 3Bosnia and Herzegovina3 cities73.7
- 4Slovenia12 cities46.6
- 5Serbia38 cities39.9
- 6Thailand85 cities, was 1636.3
- 7Poland74 cities35.4
- 8China4 cities34.2
- 9Czechia35 cities, was 3733.4
- 10The Netherlands24 cities32.4
- 11Germany253 cities32.1
- 12Belgium45 cities30.3
- 13Romania9 cities28.8
- 14Slovakia40 cities26.6
- 15Hungary10 cities26.0
- 16Bulgaria5 cities25.2
- 17Laos3 cities24.7
- 18United Kingdom4 cities23.4
- 19Austria36 cities22.5
- 20Chile45 cities22.1
+ 26 more countries, 22.0 µg/m³ and below
- 38United States831 cities7.0
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.