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 5 Oct 2026: Malawi 50.8 µg/m³, Pakistan 44.2 µg/m³ and Indonesia 34.5 µg/m³.
- 1Malawi5 cities50.8
- 2Pakistan15 cities44.2
- 3Indonesia4 cities34.5
- 4India215 cities26.7
- 5Philippines3 cities25.5
- 6Chile47 cities23.0
- 7Ghana3 cities17.3
- 8South Africa37 cities16.9
- 9Serbia8 cities15.7
- 10Montenegro5 cities15.5
- 11Bosnia and Herzegovina5 cities14.0
- 12Kazakhstan5 cities13.6
- 13Hong Kong12 cities13.3
- 14Lebanon3 cities12.9
- 15Taiwan44 cities12.8
- 16Senegal4 cities11.7
- 17Thailand72 cities11.4
- 18Mexico43 cities11.3
- 19Italy17 cities10.1
- 20South Korea134 cities10.1
+ 29 more countries, 10.0 µg/m³ and below
- 42United States893 cities5.4
Not counted on this day, too few cities measured: Martinique since 4 Oct 2026, Nepal since 21 Sep 2026, Latvia since 3 Sep 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.