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 27 Jul 2023: Tha Bo 31.7 µg/m³, Nong Khaem 16.9 µg/m³ and Bang Bo District 16.2 µg/m³.
- 1Tha BoNong Khai31.7
- 2Nong KhaemBangkok16.9
- 3Bang Bo DistrictSamut Prakan16.2
- 4Phra PradaengSamut Prakan14.6
- 5Samut SakhonSamut Sakhon14.0
- 6BangkokBangkok13.7
- 7Khlong LuangPathum Thani13.3
- 8Bang KapiBangkok12.0
- 9Samut PrakanSamut Prakan10.7
- 10Nakhon PathomNakhon Pathom10.5
- 11Mueang NonthaburiNonthaburi10.2
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.