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 19 Jan 2024: Pakistan 249.8 µg/m³, India 74.9 µg/m³ and North Macedonia 49.2 µg/m³.
- 1Pakistan4 cities249.8
- 2India5 cities74.9
- 3North Macedonia7 cities49.2
- 4Montenegro3 cities47.8
- 5China3 cities47.3
- 6Thailand60 cities, was 1036.6
- 7Serbia12 cities, was 331.8
- 8Peru5 cities28.0
- 9Bulgaria6 cities25.8
- 10Romania8 cities24.6
- 11Greece10 cities23.1
- 12Italy23 cities21.2
- 13Poland76 cities19.8
- 14Hungary10 cities19.0
- 15France133 cities18.9
- 16Chile43 cities17.7
- 17Norway21 cities17.6
- 18Hong Kong13 cities16.8
- 19Slovakia27 cities16.1
- 20Austria28 cities16.0
+ 20 more countries, 15.8 µg/m³ and below
- 35United States750 cities6.5
Not counted on this day, too few cities measured: Luxembourg since 15 Jan 2024, Reunion since 15 Jan 2024, Malta since 2 Jan 2024 and Martinique since 1 Dec 2023.
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.