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 24 Jul 2023: Tha Bo 30.9 µg/m³, Nong Khaem 15.9 µg/m³ and Bang Bo District 15.7 µg/m³.
- 1Tha BoNong Khai30.9
- 2Nong KhaemBangkok15.9
- 3Bang Bo DistrictSamut Prakan15.7
- 4Phra PradaengSamut Prakan14.0
- 5BangkokBangkok13.4
- 6Samut SakhonSamut Sakhon13.3
- 7Khlong LuangPathum Thani13.2
- 8Bang KapiBangkok11.9
- 9Nakhon PathomNakhon Pathom10.4
- 10Samut PrakanSamut Prakan10.3
- 11Mueang NonthaburiNonthaburi10.1
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.