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 19 Sep 2026: Malawi 56.2 µg/m³, Pakistan 35.8 µg/m³ and Indonesia 34.8 µg/m³.
- 1Malawi5 cities56.2
- 2Pakistan14 cities35.8
- 3Indonesia3 cities34.8
- 4Nepal3 cities28.0
- 5Chile47 cities27.3
- 6India214 cities23.3
- 7Lebanon3 cities21.5
- 8Montenegro5 cities21.3
- 9South Africa37 cities20.0
- 10Ghana3 cities18.0
- 11Mexico48 cities15.0
- 12North Macedonia15 cities14.5
- 13Serbia8 cities13.3
- 14Kazakhstan5 cities12.3
- 15Hong Kong12 cities12.2
- 16Italy21 cities11.2
- 17Thailand76 cities11.2
- 18Senegal4 cities11.0
- 19Martinique3 cities9.8
- 20Romania26 cities9.5
+ 28 more countries, 9.4 µg/m³ and below
- 32United States887 cities6.6
Not counted on this day, too few cities measured: Sweden since 13 Sep 2026, Latvia since 3 Sep 2026, Bosnia and Herzegovina since 16 Aug 2026 and Malta since 12 Aug 2026.
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.