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 17 Aug 2025: Pakistan 42.7 µg/m³, Chile 35.2 µg/m³ and Peru 27.1 µg/m³.
- 1Pakistan11 cities42.7
- 2Chile48 cities35.2
- 3Peru5 cities27.1
- 4Philippines3 cities22.7
- 5India226 cities20.2
- 6Italy28 cities18.2
- 7Ghana4 cities17.4
- 8Switzerland11 cities17.0
- 9Malta5 cities16.1
- 10Spain89 cities15.6
- 11Bosnia and Herzegovina4 cities15.4
- 12Slovakia41 cities14.9
- 13Czechia34 cities14.3
- 14Mexico39 cities13.9
- 15Slovenia12 cities13.7
- 16New Zealand10 cities13.6
- 17Luxembourg3 cities12.7
- 18Austria36 cities12.3
- 19Germany234 cities12.3
- 20France104 cities, was 10412.1
+ 26 more countries, 12.0 µg/m³ and below
- 35United States859 cities7.6
Not counted on this day, too few cities measured: China since 7 Aug 2025, Serbia since 3 Jul 2025, Thailand since 3 Jul 2025 and Taiwan since 3 Jul 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.