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 8 Jul 2026: Chile 50.5 µg/m³, Pakistan 32.0 µg/m³ and Malawi 26.3 µg/m³.
- 1Chile46 cities50.5
- 2Pakistan14 cities32.0
- 3Malawi5 cities26.3
- 4Peru6 cities25.7
- 5India209 cities25.0
- 6Lebanon3 cities18.7
- 7New Zealand6 cities14.8
- 8Brazil6 cities13.4
- 9Kazakhstan4 cities12.2
- 10Mexico45 cities12.1
- 11Slovakia39 cities11.9
- 12South Korea131 cities11.7
- 13Italy21 cities11.4
- 14Malta4 cities11.3
- 15Serbia7 cities11.1
- 16Bosnia and Herzegovina4 cities10.4
- 17Thailand69 cities10.1
- 18Senegal4 cities10.0
- 19Romania21 cities9.4
- 20Hungary4 cities, was 139.1
+ 21 more countries, 8.9 µg/m³ and below
- 30United States857 cities7.2
Not counted on this day, too few cities measured: Norway since 6 Jul 2026, Sweden since 5 Jul 2026, Greece since 14 Jun 2026 and 7 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.