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 6 Jul 2026: Chile 53.3 µg/m³, Pakistan 39.5 µg/m³ and Malawi 28.8 µg/m³.
- 1Chile45 cities53.3
- 2Pakistan14 cities39.5
- 3Malawi5 cities28.8
- 4Peru6 cities27.6
- 5Lebanon3 cities22.0
- 6India209 cities, was 22319.2
- 7New Zealand6 cities19.1
- 8Kazakhstan4 cities15.8
- 9Mexico46 cities15.4
- 10Brazil6 cities14.5
- 11Malta5 cities13.2
- 12Martinique3 cities13.1
- 13South Korea117 cities12.2
- 14Greece13 cities11.5
- 15Serbia8 cities11.2
- 16Slovakia37 cities11.0
- 17Romania28 cities, was 2710.8
- 18United States848 cities9.9
- 19North Macedonia11 cities, was 149.7
- 20Italy30 cities, was 399.6
+ 25 more countries, 9.3 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.