SmogRank / World / Asia / Japan / Chiba

Most polluted cities in Chiba, Japan

31 measured cities, last 30 days; 0 above the WHO 24-hour guideline. Worst: Sukayama at 7.6 µg/m³, #1,091 in the world.

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.

Gunma: 8 measured citiesIbaraki: 19 measured citiesKanagawa: 21 measured citiesSaitama: 31 measured citiesTochigi: 9 measured citiesTokyo: 10 measured citiesChiba: 31 measured cities#31 Tōgane: 4.5 µg/m³#29 Yotsukaidō: 4.6 µg/m³#30 Ajiki: 4.6 µg/m³#25 Yachimata: 4.8 µg/m³#26 Kōzaki: 4.8 µg/m³#27 Katsuura: 4.8 µg/m³#28 Baraki: 4.8 µg/m³#23 Omigawa: 4.9 µg/m³#24 Sodegaura: 4.9 µg/m³#20 Matsudo: 5.0 µg/m³#21 Ōami: 5.0 µg/m³#22 Narashino: 5.0 µg/m³#19 Sōsa: 5.1 µg/m³#18 Narita: 5.2 µg/m³#14 Tateyama: 5.4 µg/m³#15 Yokoshiba: 5.4 µg/m³#16 Yachiyo: 5.4 µg/m³#17 Motona: 5.4 µg/m³#13 Noda: 5.5 µg/m³#11 Kashiwa: 5.6 µg/m³#12 Inzai: 5.6 µg/m³#8 Urayasu: 5.7 µg/m³#9 Kisarazu: 5.7 µg/m³#10 Chiba: 5.7 µg/m³#7 Mobara: 5.8 µg/m³#5 Ichinomiya: 5.9 µg/m³#6 Kamagaya: 5.9 µg/m³#3 Sakura: 6.0 µg/m³#4 Ichihara: 6.0 µg/m³#2 Kimitsu: 6.6 µg/m³#1 Sukayama: 7.6 µg/m³
Each dot is a measured city, coloured by its PM2.5; tap a dot to open the city.
← Sukayama 0% 0.75%0
Every measured city in Chiba, Japan, 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. 1Sukayamalast full day 2 Oct 0%
  2. 2Kimitsu 0%
  3. 3Sakura 0%
  4. 3Ichihara 0%
  5. 5Ichinomiyalast full day 2 Oct 0%
  6. 5Kamagaya 0%
  7. 7Mobaralast full day 3 Oct 0%
  8. 8Urayasu 0%
  9. 8Kisarazu 0%
  10. 8Chiba 0%
  11. 11Kashiwa 0%
  12. 11Inzai 0%
  13. 13Noda 0%
  14. 14Tateyama 0%
  15. 14Yokoshibalast full day 2 Oct 0%
  16. 14Yachiyo 0%
  17. 14Motona 0%
  18. 18Narita 0%
  19. 19Sōsa 0%
  20. 20Matsudo 0%
  21. 20Ōami 0%
  22. 20Narashino 0%
  23. 23Omigawa 0%
  24. 23Sodegaura 0%
  25. 25Yachimata 0%
  26. 25Kōzaki 0%
  27. 25Katsuura 0%
  28. 25Barakilast full day 2 Oct 0%
  29. 29Yotsukaidō 0%
  30. 29Ajikilast full day 2 Oct 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

Estimated: cities without a monitor

Chiba cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.

City7-day estimateBand
Nagareyama≈ 5 µg/m³Good
Abiko≈ 5 µg/m³Good
Katori-shi≈ 5 µg/m³Good
Asahi≈ 5 µg/m³Good
Shiroi≈ 7 µg/m³Good
Choshi≈ 5 µg/m³Good
Futtsu≈ 4 µg/m³Good
Ryōgoku≈ 4 µg/m³Good
Sanmu≈ 5 µg/m³Good
Ōamishirasato≈ 5 µg/m³Good
Sawara≈ 5 µg/m³Good
Hasaki≈ 5 µg/m³Good
Minamibōsō≈ 5 µg/m³Good
Isumi≈ 4 µg/m³Good
Yōkaichiba≈ 5 µg/m³Good
Kamogawa≈ 5 µg/m³Good
Makuhari≈ 6 µg/m³Good
Narutō≈ 5 µg/m³Good
Shisui≈ 4 µg/m³Good
Ōhara≈ 4 µg/m³Good
Minaminagareyama≈ 5 µg/m³Good

Bad-air episodes in Chiba

Times when many cities around here had PM2.5 at twice their usual or more on the same days.

Use this board

SmogRank, most polluted cities in Chiba, Japan, PM2.5, last 30 days to 6 Oct 2026, 22:00 UTC, smogrank.com/jp/region/chiba?w=30d.

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Updated 2026-10-06 22:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.