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 3 Jul 2024: Chile 43.3 µg/m³, Pakistan 37.1 µg/m³ and China 21.4 µg/m³.
- 1Chile41 cities43.3
- 2Pakistan3 cities37.1
- 3China4 cities21.4
- 4Peru15 cities20.9
- 5India4 cities18.1
- 6New Zealand5 cities13.6
- 7Malta5 cities13.0
- 8Thailand16 cities, was 7912.6
- 9Italy9 cities, was 3811.7
- 10South Korea141 cities11.7
- 11Slovakia35 cities11.7
- 12Serbia23 cities11.6
- 13Singapore5 cities10.8
- 14Hungary10 cities10.4
- 15Poland72 cities10.0
- 16Greece9 cities9.9
- 17North Macedonia8 cities9.4
- 18Belgium37 cities8.9
- 19Germany203 cities8.6
- 20Bosnia and Herzegovina5 cities8.5
+ 20 more countries, 8.0 µg/m³ and below
- 35United States771 cities5.3
Not counted on this day, too few cities measured: Luxembourg since 3 Jul 2024, Estonia since 1 Jul 2024, Slovenia since 30 Jun 2024 and 8 more countries.
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.