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 7 days to 11 Sep 2026: Malawi 49.3 µg/m³, Pakistan 40.1 µg/m³ and Montenegro 34.3 µg/m³.
- 1Malawi5 cities49.3
- 2Pakistan15 cities40.1
- 3Montenegro5 cities34.3
- 4Nepal3 cities30.1
- 5Indonesia4 cities26.9
- 6Chile48 cities26.0
- 7Nigeria3 cities23.9
- 8India223 cities, was 21223.6
- 9Lebanon3 cities20.6
- 10Hong Kong12 cities16.1
- 11South Africa38 cities15.0
- 12Bosnia and Herzegovina5 cities14.2
- 13Kazakhstan5 cities14.2
- 14Mexico46 cities14.0
- 15Senegal4 cities13.9
- 16Serbia7 cities13.6
- 17North Macedonia14 cities13.1
- 18Thailand75 cities10.9
- 19Taiwan44 cities10.8
- 20Italy14 cities10.5
+ 28 more countries, 8.9 µg/m³ and below
- 32United States876 cities5.5
Not counted on this day, too few cities measured: Ghana since 11 Sep 2026, Kyrgyzstan since 11 Sep 2026, Martinique since 11 Sep 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.