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 to11 Oct 2025 That day's board

The worst cities in Thailand for PM2.5 over the 30 days to 11 Oct 2025: Bang Na 21.6 µg/m³, Bueng Kum 20.0 µg/m³ and Ban Thai Tan 18.6 µg/m³.

  1. 1Bang NaBangkok21.6
  2. 2Bueng KumBangkok20.0
  3. 3Ban Thai TanAng Thong18.6
  4. 4Sing BuriSing Buri17.8
  5. 5Khlong Sam WaBangkok17.3
  6. 6Si Maha PhotPrachin Buri17.2
  7. 7Khan Na YaoBangkok17.0
  8. 8Saphan SungBangkok16.7
  9. 9Ban Samae DamBangkok16.3
  10. 10Khlong LuangPathum Thani16.1
  11. 11Bang KapiBangkok15.7
  12. 12KalasinKalasin15.5
  13. 13Ban ChangRayong15.2
  14. 14Phra PradaengSamut Prakan15.0
  15. 15Nong KhaemBangkok15.0
  16. 16Maha SarakhamMaha Sarakham14.8
  17. 17Lat KrabangBangkok14.5
  18. 18Samut SakhonSamut Sakhon14.2
  19. 19YasothonYasothon13.9
  20. 20Amnat CharoenAmnat Charoen13.3

+ 55 more cities, 12.8 µg/m³ and below

Not counted on this day, too few days measured: Saraburi since 11 Oct 2025.

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.