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 11 Jul 2026: Chile 52.0 µg/m³, Pakistan 31.8 µg/m³ and Malawi 27.7 µg/m³.
- 1Chile46 cities52.0
- 2Pakistan15 cities31.8
- 3Malawi5 cities27.7
- 4Peru6 cities25.6
- 5India205 cities24.1
- 6Lebanon3 cities17.5
- 7New Zealand6 cities14.2
- 8Kazakhstan4 cities12.9
- 9Brazil6 cities12.8
- 10Mexico45 cities12.4
- 11Italy30 cities11.6
- 12Martinique3 cities11.6
- 13Slovakia39 cities11.5
- 14South Korea131 cities11.4
- 15Malta4 cities11.4
- 16Serbia8 cities10.7
- 17Bosnia and Herzegovina4 cities10.4
- 18Senegal4 cities9.5
- 19Romania24 cities9.0
- 20Montenegro4 cities8.9
+ 22 more countries, 8.8 µg/m³ and below
- 29United States861 cities7.3
Not counted on this day, too few cities measured: Thailand since 11 Jul 2026, Norway since 6 Jul 2026, Sweden since 5 Jul 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.