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 8 Feb 2025: India 79.4 µg/m³, Pakistan 75.8 µg/m³ and Bosnia and Herzegovina 64.9 µg/m³.
- 1India5 cities79.4
- 2Pakistan4 cities75.8
- 3Bosnia and Herzegovina3 cities64.9
- 4Serbia25 cities49.1
- 5Thailand84 cities, was 1640.2
- 6Croatia4 cities35.6
- 7Slovenia12 cities31.3
- 8Poland77 cities29.5
- 9China4 cities28.7
- 10Hungary10 cities27.0
- 11Slovakia41 cities25.7
- 12Czechia36 cities, was 3725.3
- 13The Netherlands24 cities21.0
- 14Austria36 cities20.7
- 15Belgium45 cities20.5
- 16Chile45 cities19.6
- 17Germany246 cities19.6
- 18Switzerland9 cities, was 1019.3
- 19Peru4 cities, was 1619.0
- 20Romania8 cities18.6
+ 25 more countries, 17.0 µg/m³ and below
- 38United States811 cities6.7
Not counted on this day, too few cities measured: Laos since 7 Feb 2025, 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.