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 23 Jul 2026: Chile 45.4 µg/m³, Malawi 36.1 µg/m³ and Pakistan 31.1 µg/m³.
- 1Chile44 cities45.4
- 2Malawi5 cities36.1
- 3Pakistan13 cities31.1
- 4India209 cities23.0
- 5Lebanon3 cities21.7
- 6New Zealand6 cities17.0
- 7Mexico47 cities14.6
- 8Malta5 cities13.8
- 9Kazakhstan4 cities13.3
- 10Martinique3 cities12.5
- 11Brazil6 cities12.4
- 12Italy31 cities12.1
- 13South Korea133 cities11.5
- 14Serbia8 cities11.4
- 15Bosnia and Herzegovina5 cities10.9
- 16Slovakia39 cities10.7
- 17Canada117 cities10.6
- 18Japan566 cities10.2
- 19Montenegro4 cities10.2
- 20Spain5 cities10.1
+ 24 more countries, 10.1 µg/m³ and below
- 23United States864 cities9.9
Not counted on this day, too few cities measured: Latvia since 21 Jul 2026, Peru since 17 Jul 2026, Thailand since 11 Jul 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.