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 4 Jul 2026: Chile 51.1 µg/m³, Pakistan 37.5 µg/m³ and Malawi 31.8 µg/m³.
- 1Chile46 cities51.1
- 2Pakistan14 cities37.5
- 3Malawi5 cities31.8
- 4Peru6 cities30.0
- 5Lebanon3 cities22.6
- 6India224 cities, was 22322.0
- 7New Zealand6 cities21.1
- 8Brazil6 cities18.0
- 9Mexico47 cities15.4
- 10Kazakhstan4 cities14.9
- 11Slovakia35 cities14.9
- 12Malta5 cities14.6
- 13South Korea128 cities13.6
- 14Serbia8 cities12.7
- 15Martinique3 cities12.4
- 16Romania23 cities, was 2712.4
- 17Bosnia and Herzegovina5 cities12.2
- 18Greece12 cities11.6
- 19Hungary11 cities, was 1311.1
- 20North Macedonia11 cities, was 1410.8
+ 25 more countries, 10.8 µg/m³ and below
- 24United States856 cities9.9
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.