SmogRank / History / City race
Cities in Thailand, worst air first, day by day
Each measured city's average over the 30 days to every day since January 2023, worst first. Find your own city to follow it through the race, or keep to one country.
The worst cities in Thailand for PM2.5 over the 30 days to 28 Apr 2023: Bang Khun Thian 59.5 µg/m³, Nong Khaem 38.7 µg/m³ and Samut Prakan 36.7 µg/m³.
- 1Bang Khun ThianBangkok59.5
- 2Nong KhaemBangkok38.7
- 3Samut PrakanSamut Prakan36.7
- 4Nakhon PathomNakhon Pathom36.7
- 5BangkokBangkok36.2
- 6Khlong LuangPathum Thani34.4
- 7Bang KapiBangkok34.1
- 8Mueang NonthaburiNonthaburi33.3
- 9Samut SakhonSamut Sakhon32.0
- 10Phra PradaengSamut Prakan31.1
- 11Bang Bo DistrictSamut Prakan28.8
Not counted on this day, too few days measured: Trang since 26 Apr 2023, Sukhothai since 26 Apr 2023, Ratchaburi since 26 Apr 2023 and 38 more cities. Days missing from the source archive fall in this window, so fewer countries are counted.
Cities counted each day
A city's number is its average over the 30 days, shown only when 21 of them were measured (5 of 7 on the 7-day race), the same minimum as the 30- and 7-day boards. A city whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air. 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.