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 13 Mar 2026: Pakistan 79.8 µg/m³, Kyrgyzstan 74.4 µg/m³ and Kazakhstan 51.6 µg/m³.
- 1Pakistan12 cities79.8
- 2Kyrgyzstan3 cities74.4
- 3Kazakhstan4 cities51.6
- 4India225 cities, was 23946.9
- 5Poland59 cities33.3
- 6Laos3 cities32.3
- 7Czechia3 cities29.2
- 8Latvia4 cities28.1
- 9Ghana4 cities27.7
- 10Thailand83 cities27.1
- 11North Macedonia15 cities26.8
- 12South Korea141 cities26.3
- 13Montenegro5 cities24.8
- 14Bosnia and Herzegovina5 cities23.4
- 15Mexico51 cities21.9
- 16The Netherlands37 cities21.4
- 17Peru6 cities20.7
- 18Hungary13 cities20.6
- 19Serbia4 cities20.5
- 20Hong Kong13 cities20.0
+ 29 more countries, 19.1 µg/m³ and below
- 44United States870 cities5.3
Not counted on this day, too few cities measured: Luxembourg since 11 Mar 2026, Spain since 11 Feb 2026 and Martinique since 30 Jan 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.