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 21 Jun 2026: Chile 49.3 µg/m³, Pakistan 30.7 µg/m³ and India 29.1 µg/m³.
- 1Chile46 cities49.3
- 2Pakistan13 cities30.7
- 3India230 cities29.1
- 4Peru6 cities24.8
- 5Malawi5 cities24.3
- 6Lebanon3 cities15.4
- 7Senegal4 cities14.6
- 8South Korea136 cities13.5
- 9New Zealand6 cities13.3
- 10Mexico45 cities12.6
- 11Kazakhstan4 cities11.9
- 12Brazil6 cities11.6
- 13Thailand78 cities11.2
- 14Malta4 cities11.1
- 15Italy16 cities, was 910.4
- 16Hungary4 cities, was 1310.1
- 17Serbia8 cities9.4
- 18Slovakia37 cities9.1
- 19Taiwan44 cities9.0
- 20Bosnia and Herzegovina3 cities8.7
+ 20 more countries, 8.7 µg/m³ and below
- 29United States848 cities5.6
Not counted on this day, too few cities measured: Belgium since 14 Jun 2026, Greece since 14 Jun 2026, Estonia since 13 Jun 2026 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.