SmogRank / World / Japan / Chiba / October 2025

Most polluted cities in Chiba, Japan, October 2025

31 cities in Chiba, Japan ranked by their average PM2.5 over the 31 days. Worst: Sukayama at 9.4 µg/m³, #589 of 2,564 cities in the world. Cleanest: Tōgane at 5.5. A city needs measurements on 70% of the days to be ranked.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

← Sukayama 0% 0.75%0
Every city in Chiba, Japan ranked for October 2025, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1Sukayama
    0%
  2. 2Noda
    0%
  3. 3Kimitsu
    0%
  4. 4Kamagaya
    0%
  5. 5Ichihara
    0%
  6. 6Kisarazu
    0%
  7. 6Kashiwa
    0%
  8. 6Sakura
    0%
  9. 6Yachiyo
    0%
  10. 10Urayasu
    0%
  11. 10Chiba
    0%
  12. 12Inzai
    0%
  13. 13Yachimata
    0%
  14. 13Baraki
    0%
  15. 13Motona
    0%
  16. 16Mobara
    0%
  17. 17Narita
    0%
  18. 17Ichinomiya
    0%
  19. 17Narashino
    0%
  20. 20Matsudo
    0%
  21. 20Yotsukaidō
    0%
  22. 22Kōzaki
    0%
  23. 22Sodegaura
    0%
  24. 24Tateyama
    0%
  25. 24Ajiki
    0%
  26. 26Yokoshiba
    0%
  27. 27Omigawa
    0%
  28. 28Katsuura
    0%
  29. 28Sōsa
    0%
  30. 30Nagadomi
    0%
  31. 31Tōgane
    0%
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

All cities in the world, October 2025 · All cities in Japan, October 2025 · Chiba now

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SmogRank, most polluted cities in Chiba, Japan, PM2.5, October 2025, smogrank.com/jp/region/chiba/history/2025-10 (accessed 7 Oct 2026).

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