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 13 Jul 2024: Chile 59.6 µg/m³, Pakistan 35.5 µg/m³ and Peru 24.7 µg/m³.
- 1Chile37 cities59.6
- 2Pakistan4 cities35.5
- 3Peru15 cities24.7
- 4China3 cities24.5
- 5Bosnia and Herzegovina5 cities19.8
- 6New Zealand5 cities19.4
- 7India4 cities18.1
- 8Malta5 cities16.3
- 9Slovenia12 cities15.7
- 10Slovakia39 cities15.6
- 11Serbia24 cities14.6
- 12Italy8 cities, was 3814.5
- 13Hungary11 cities14.4
- 14North Macedonia9 cities13.5
- 15Thailand14 cities, was 7912.9
- 16South Korea141 cities12.7
- 17Greece6 cities12.0
- 18Czechia35 cities11.0
- 19Romania9 cities10.9
- 20Singapore5 cities10.3
+ 27 more countries, 9.7 µg/m³ and below
- 24United States782 cities8.2
Not counted on this day, too few cities measured: Croatia since 1 Jun 2024, Laos since 29 May 2024 and Puerto Rico since 23 May 2024.
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.