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 7 Oct 2026: Pakistan 55.7 µg/m³, India 36.0 µg/m³ and Nigeria 30.1 µg/m³.
- 1Pakistan15 cities55.7
- 2India163 cities36.0
- 3Nigeria3 cities30.1
- 4Malawi4 cities27.3
- 5Indonesia4 cities25.4
- 6Kazakhstan4 cities23.6
- 7Serbia8 cities23.1
- 8Ghana3 cities22.1
- 9Chile44 cities19.6
- 10Italy13 cities16.2
- 11Slovakia32 cities15.2
- 12Montenegro5 cities15.1
- 13Thailand71 cities14.6
- 14Hungary10 cities14.3
- 15Bosnia and Herzegovina3 cities13.4
- 16North Macedonia9 cities13.3
- 17Austria37 cities12.7
- 18Romania13 cities12.5
- 19Taiwan42 cities12.4
- 20South Africa39 cities11.6
+ 27 more countries, 11.3 µg/m³ and below
- 43United States730 cities5.7
Not counted on this day, too few cities measured: Philippines since 7 Oct 2026, Ireland since 6 Oct 2026, Portugal since 6 Oct 2026 and 6 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.