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 19 Oct 2024: Pakistan 82.0 µg/m³, India 31.9 µg/m³ and China 31.0 µg/m³.
- 1Pakistan4 cities82.0
- 2India5 cities31.9
- 3China4 cities31.0
- 4Chile46 cities20.6
- 5Thailand15 cities, was 6620.4
- 6Peru15 cities19.5
- 7Hungary4 cities16.2
- 8Serbia20 cities15.2
- 9Taiwan42 cities14.7
- 10Hong Kong13 cities14.2
- 11Singapore5 cities13.6
- 12Poland73 cities12.9
- 13South Korea138 cities12.2
- 14Mexico12 cities, was 312.1
- 15Japan550 cities8.0
- 16The Netherlands22 cities7.3
- 17Norway18 cities7.3
- 18New Zealand7 cities6.5
- 19United Kingdom60 cities6.3
- 20United States781 cities6.2
+ 4 more countries, 6.0 µg/m³ and below
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.