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 18 Mar 2026: Kyrgyzstan 149.7 µg/m³, Kazakhstan 52.0 µg/m³ and Pakistan 46.6 µg/m³.
- 1Kyrgyzstan3 cities149.7
- 2Kazakhstan4 cities52.0
- 3Pakistan13 cities46.6
- 4India241 cities, was 23939.4
- 5Laos3 cities30.9
- 6South Korea141 cities29.7
- 7Thailand80 cities26.2
- 8North Macedonia14 cities25.0
- 9Montenegro5 cities23.5
- 10Poland58 cities22.5
- 11Peru5 cities22.1
- 12Ghana4 cities21.6
- 13Serbia4 cities21.2
- 14Mexico52 cities19.2
- 15Latvia4 cities18.9
- 16Chile47 cities18.6
- 17Hong Kong13 cities16.9
- 18Taiwan43 cities16.9
- 19Hungary12 cities16.8
- 20Philippines3 cities16.7
+ 28 more countries, 15.9 µg/m³ and below
- 45United States865 cities4.6
Not counted on this day, too few cities measured: Czechia since 18 Mar 2026, Romania since 15 Mar 2026, Luxembourg since 11 Mar 2026 and 2 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.