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 30 days to 9 Jun 2026: Chile 51.2 µg/m³, Pakistan 35.3 µg/m³ and India 33.1 µg/m³.
- 1Chile46 cities51.2
- 2Pakistan14 cities35.3
- 3India225 cities33.1
- 4Peru6 cities25.8
- 5Malawi5 cities20.4
- 6Mexico40 cities16.4
- 7South Korea134 cities14.4
- 8Laos3 cities14.0
- 9Senegal4 cities14.0
- 10Lebanon3 cities13.7
- 11Kazakhstan4 cities13.2
- 12Thailand79 cities12.4
- 13New Zealand6 cities12.3
- 14Brazil6 cities11.1
- 15Taiwan44 cities11.0
- 16Malta5 cities10.3
- 17Serbia8 cities10.1
- 18Greece9 cities8.8
- 19Italy34 cities, was 98.6
- 20Japan572 cities8.4
+ 25 more countries, 8.4 µg/m³ and below
- 28United States858 cities5.9
Not counted on this day, too few cities measured: Martinique since 8 Jun 2026, Hong Kong since 7 Jun 2026, Latvia since 7 Jun 2026 and 4 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.