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 16 Jun 2026: Chile 40.3 µg/m³, Pakistan 30.1 µg/m³ and India 29.2 µg/m³.
- 1Chile46 cities40.3
- 2Pakistan13 cities30.1
- 3India227 cities29.2
- 4Malawi5 cities24.6
- 5Peru6 cities23.9
- 6Lebanon3 cities16.3
- 7Brazil6 cities16.0
- 8South Korea133 cities14.1
- 9New Zealand6 cities14.1
- 10Senegal4 cities12.6
- 11Kazakhstan4 cities10.5
- 12Malta3 cities10.0
- 13Thailand76 cities9.5
- 14Japan571 cities9.4
- 15Mexico46 cities8.8
- 16Hungary4 cities, was 137.3
- 17Serbia8 cities7.1
- 18Romania19 cities6.3
- 19North Macedonia6 cities6.1
- 20Slovakia20 cities5.7
+ 13 more countries, 5.4 µg/m³ and below
- 21United States831 cities5.4
Not counted on this day, too few cities measured: Bosnia and Herzegovina since 10 Jun 2026, Switzerland since 10 Jun 2026, Ireland since 10 Jun 2026 and 17 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.