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.

CountriesCities
The 30 days to25 Apr 2023 That day's board

The worst cities in Thailand for PM2.5 over the 30 days to 25 Apr 2023: Mae Sai 256.4 µg/m³, Chiang Mai 126.7 µg/m³ and Loei 86.0 µg/m³.

  1. 1Mae SaiChiang Rai256.4
  2. 2Chiang MaiChiang Mai126.7
  3. 3LoeiLoei86.0
  4. 4SukhothaiSukhothai66.2
  5. 5UttaraditUttaradit65.7
  6. 6Bueng KanBueng Kan62.8
  7. 7Bang Khun ThianBangkok57.0
  8. 8PhichitPhichit55.4
  9. 9Ubon RatchathaniUbon Ratchathani52.5
  10. 10Lop BuriLopburi46.5
  11. 11Suphan BuriSuphan Buri45.4
  12. 12RatchaburiRatchaburi40.6
  13. 13Bang NaBangkok38.5
  14. 14Sakon NakhonSakon Nakhon37.3
  15. 15Phra Nakhon Si AyutthayaPhra Nakhon Si Ayutthaya37.2
  16. 16Nong KhaemBangkok37.1
  17. 17Khlong Sam WaBangkok35.5
  18. 18Nakhon PathomNakhon Pathom35.3
  19. 19Samut PrakanSamut Prakan34.8
  20. 20BangkokBangkok34.7

+ 19 more cities, 32.8 µg/m³ and below

Not counted on this day, too few days measured: Kanchanaburi since 25 Apr 2023, Chiang Rai since 25 Apr 2023, Si Sa Ket since 25 Apr 2023 and 10 more cities. Days missing from the source archive fall in this window, so fewer countries are counted.

30 days7 days
GoodModerateSensitive groupsUnhealthyVery unhealthyHazardousWHO 24-hour guideline, 15 µg/m³Fades where it stood: not counted that 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.