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 6 Jun 2026: Chile 41.8 µg/m³, Pakistan 31.0 µg/m³ and Peru 30.9 µg/m³.
- 1Chile46 cities41.8
- 2Pakistan13 cities31.0
- 3Peru5 cities30.9
- 4India224 cities29.2
- 5Malawi5 cities19.9
- 6Lebanon3 cities15.1
- 7South Korea135 cities15.0
- 8Senegal4 cities14.5
- 9Mexico42 cities13.7
- 10Taiwan44 cities13.0
- 11Thailand79 cities12.6
- 12Malta5 cities12.0
- 13Greece15 cities10.2
- 14Serbia8 cities9.2
- 15Italy38 cities9.0
- 16New Zealand6 cities8.9
- 17North Macedonia11 cities8.6
- 18Kazakhstan4 cities8.5
- 19Brazil6 cities8.3
- 20Hungary13 cities7.9
+ 25 more countries, 7.8 µg/m³ and below
- 25United States848 cities6.5
Not counted on this day, too few cities measured: Czechia since 6 Jun 2026, Martinique since 6 Jun 2026, Poland since 5 Jun 2026 and 5 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.