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 17 Jan 2026: Pakistan 192.7 µg/m³, Kazakhstan 78.4 µg/m³ and India 64.1 µg/m³.
- 1Pakistan12 cities192.7
- 2Kazakhstan4 cities78.4
- 3India183 cities64.1
- 4Montenegro4 cities53.5
- 5Bosnia and Herzegovina5 cities49.7
- 6North Macedonia13 cities48.3
- 7Ghana3 cities36.3
- 8Thailand76 cities29.5
- 9Peru6 cities24.7
- 10Romania24 cities24.6
- 11Hong Kong13 cities24.5
- 12Poland58 cities24.0
- 13Hungary13 cities22.4
- 14Mexico43 cities21.5
- 15Laos3 cities19.5
- 16Slovenia12 cities19.4
- 17South Korea140 cities18.7
- 18Bulgaria7 cities17.4
- 19Chile43 cities17.2
- 20Philippines3 cities16.1
+ 24 more countries, 16.0 µg/m³ and below
- 37United States874 cities7.0
Not counted on this day, too few cities measured: Senegal since 17 Jan 2026, Slovakia since 9 Jan 2026, Czechia since 7 Jan 2026 and 4 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.