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 11 Feb 2025: India 82.5 µg/m³, Bosnia and Herzegovina 80.5 µg/m³ and Pakistan 77.5 µg/m³.
- 1India5 cities82.5
- 2Bosnia and Herzegovina3 cities80.5
- 3Pakistan4 cities77.5
- 4Slovenia12 cities45.2
- 5Serbia32 cities44.8
- 6Thailand82 cities, was 1632.7
- 7Poland75 cities32.2
- 8China4 cities30.4
- 9Hungary10 cities30.4
- 10Czechia35 cities, was 3728.5
- 11Slovakia42 cities28.0
- 12Germany253 cities25.9
- 13The Netherlands24 cities24.3
- 14Switzerland9 cities, was 1023.6
- 15Croatia3 cities23.5
- 16Austria36 cities22.5
- 17Belgium45 cities22.5
- 18Chile46 cities21.6
- 19Mexico11 cities20.1
- 20Romania9 cities20.1
+ 25 more countries, 19.2 µg/m³ and below
- 38United States831 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.