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 Jul 2026: Chile 57.0 µg/m³, Pakistan 39.5 µg/m³ and Peru 27.6 µg/m³.
- 1Chile44 cities57.0
- 2Pakistan13 cities39.5
- 3Peru6 cities27.6
- 4Malawi5 cities26.7
- 5Lebanon3 cities22.1
- 6India212 cities, was 22318.6
- 7New Zealand6 cities15.9
- 8Mexico46 cities15.0
- 9Kazakhstan4 cities14.9
- 10Martinique3 cities13.4
- 11Brazil6 cities12.5
- 12Malta5 cities12.0
- 13South Korea115 cities11.7
- 14Greece11 cities10.9
- 15Serbia8 cities10.0
- 16Romania26 cities, was 279.4
- 17United States848 cities9.4
- 18North Macedonia11 cities, was 149.1
- 19Italy30 cities, was 398.9
- 20Slovakia38 cities8.8
+ 25 more countries, 8.3 µg/m³ and below
Not counted on this day, too few cities measured: Latvia since 4 Jul 2026, Norway since 4 Jul 2026, Thailand since 4 Jul 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.