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 Jun 2026: Chile 43.7 µg/m³, Pakistan 35.9 µg/m³ and India 28.7 µg/m³.
- 1Chile46 cities43.7
- 2Pakistan13 cities35.9
- 3India226 cities28.7
- 4Peru5 cities27.7
- 5Malawi5 cities23.9
- 6Lebanon3 cities15.1
- 7South Korea135 cities14.2
- 8Senegal4 cities13.8
- 9Mexico45 cities13.4
- 10Malta4 cities12.7
- 11Taiwan44 cities12.0
- 12Thailand78 cities11.9
- 13New Zealand6 cities10.6
- 14Brazil6 cities10.5
- 15Greece15 cities10.4
- 16Serbia8 cities9.8
- 17Kazakhstan4 cities9.3
- 18North Macedonia10 cities9.0
- 19Italy37 cities8.8
- 20Hungary12 cities7.8
+ 24 more countries, 7.8 µg/m³ and below
- 24United States842 cities6.8
Not counted on this day, too few cities measured: Latvia since 7 Jun 2026, Czechia since 6 Jun 2026, Martinique since 6 Jun 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.