SmogRank / Japan / Chiba

Air quality in Minamibōsō

Chiba, Japan. PM2.5 from 1 reference monitor, updated hourly.

44US AQI
Good

Latest hour (05:00 UTC), 0.5× the WHO 24-hour guideline. PM2.5 8.0 µg/m³. 24-hour average 7.6 µg/m³.

Rank among 1,251 cities

24 hours#619of 1,251, at 42 US AQI (7.6 µg/m³)
7 days#1,653of 2,594, at 37 US AQI (6.6 µg/m³) ▼303
30 days#1,953of 2,622, at 29 US AQI (5.3 µg/m³) ▼326
This year#2,008of 2,447, at 39 US AQI (7.1 µg/m³) ▼268

The last 12 months, day by day

1102031Nov 2025DecJan 2026FebMarAprMayJunJulAugSepOct2025-11-01: 4.2 µg/m³2025-11-02: 6.6 µg/m³2025-11-03: 5.0 µg/m³2025-11-04: 3.8 µg/m³2025-11-05: 9.2 µg/m³2025-11-06: no data2025-11-07: no data2025-11-08: no data2025-11-09: no data2025-11-10: no data2025-11-11: 4.1 µg/m³2025-11-12: 5.9 µg/m³2025-11-13: 10.8 µg/m³2025-11-14: 12.2 µg/m³2025-11-15: 8.7 µg/m³2025-11-16: 8.2 µg/m³2025-11-17: 12.3 µg/m³2025-11-18: 5.9 µg/m³2025-11-19: 5.2 µg/m³2025-11-20: 7.5 µg/m³2025-11-21: 9.9 µg/m³2025-11-22: 6.5 µg/m³2025-11-23: 9.2 µg/m³2025-11-24: 11.9 µg/m³2025-11-25: 13.6 µg/m³2025-11-26: 8.6 µg/m³2025-11-27: 12.1 µg/m³2025-11-28: 7.8 µg/m³2025-11-29: 4.8 µg/m³2025-11-30: 8.6 µg/m³2025-12-01: 9.6 µg/m³2025-12-02: 18.1 µg/m³2025-12-03: 14.5 µg/m³2025-12-04: 3.0 µg/m³2025-12-05: 4.3 µg/m³2025-12-06: 6.2 µg/m³2025-12-07: 6.1 µg/m³2025-12-08: 10.6 µg/m³2025-12-09: 3.4 µg/m³2025-12-10: 6.7 µg/m³2025-12-11: 5.6 µg/m³2025-12-12: 3.1 µg/m³2025-12-13: 2.8 µg/m³2025-12-14: 7.1 µg/m³2025-12-15: 2.8 µg/m³2025-12-16: 3.3 µg/m³2025-12-17: 8.0 µg/m³2025-12-18: 5.4 µg/m³2025-12-19: 7.1 µg/m³2025-12-20: 11.5 µg/m³2025-12-21: 3.0 µg/m³2025-12-22: 4.6 µg/m³2025-12-23: 5.7 µg/m³2025-12-24: 8.9 µg/m³2025-12-25: 11.0 µg/m³2025-12-26: 3.1 µg/m³2025-12-27: 5.8 µg/m³2025-12-28: 6.8 µg/m³2025-12-29: 5.6 µg/m³2025-12-30: 9.8 µg/m³2025-12-31: 10.2 µg/m³2026-01-01: 3.2 µg/m³2026-01-02: 2.8 µg/m³2026-01-03: 2.3 µg/m³2026-01-04: 3.5 µg/m³2026-01-05: 7.5 µg/m³2026-01-06: 3.1 µg/m³2026-01-07: 7.4 µg/m³2026-01-08: 5.1 µg/m³2026-01-09: 2.6 µg/m³2026-01-10: 5.6 µg/m³2026-01-11: 6.9 µg/m³2026-01-12: 2.4 µg/m³2026-01-13: 6.7 µg/m³2026-01-14: 4.5 µg/m³2026-01-15: no data2026-01-16: no data2026-01-17: 11.0 µg/m³2026-01-18: 4.1 µg/m³2026-01-19: no data2026-01-20: 7.1 µg/m³2026-01-21: 2.8 µg/m³2026-01-22: 2.6 µg/m³2026-01-23: 2.6 µg/m³2026-01-24: no data2026-01-25: no data2026-01-26: 2.0 µg/m³2026-01-27: 5.6 µg/m³2026-01-28: 3.6 µg/m³2026-01-29: no data2026-01-30: 3.6 µg/m³2026-01-31: 3.3 µg/m³2026-02-01: 3.0 µg/m³2026-02-02: 6.1 µg/m³2026-02-03: 4.3 µg/m³2026-02-04: 5.0 µg/m³2026-02-05: 11.8 µg/m³2026-02-06: 11.5 µg/m³2026-02-07: 3.8 µg/m³2026-02-08: 4.1 µg/m³2026-02-09: 2.2 µg/m³2026-02-10: 4.4 µg/m³2026-02-11: 6.8 µg/m³2026-02-12: 6.2 µg/m³2026-02-13: 7.9 µg/m³2026-02-14: 11.2 µg/m³2026-02-15: 12.1 µg/m³2026-02-16: 14.4 µg/m³2026-02-17: 4.9 µg/m³2026-02-18: 9.4 µg/m³2026-02-19: 4.1 µg/m³2026-02-20: 6.9 µg/m³2026-02-21: 12.0 µg/m³2026-02-22: 8.6 µg/m³2026-02-23: 11.2 µg/m³2026-02-24: 14.0 µg/m³2026-02-25: 4.4 µg/m³2026-02-26: 4.9 µg/m³2026-02-27: 4.6 µg/m³2026-02-28: 7.4 µg/m³2026-03-01: 4.7 µg/m³2026-03-02: 7.8 µg/m³2026-03-03: 3.8 µg/m³2026-03-04: 2.1 µg/m³2026-03-05: 3.0 µg/m³2026-03-06: 5.1 µg/m³2026-03-07: 4.7 µg/m³2026-03-08: 5.5 µg/m³2026-03-09: 6.0 µg/m³2026-03-10: 5.6 µg/m³2026-03-11: no data2026-03-12: no data2026-03-13: 6.5 µg/m³2026-03-14: 2.8 µg/m³2026-03-15: 3.1 µg/m³2026-03-16: 4.6 µg/m³2026-03-17: 7.7 µg/m³2026-03-18: 6.3 µg/m³2026-03-19: 10.4 µg/m³2026-03-20: 9.3 µg/m³2026-03-21: 12.8 µg/m³2026-03-22: 13.6 µg/m³2026-03-23: 7.6 µg/m³2026-03-24: 12.4 µg/m³2026-03-25: 10.4 µg/m³2026-03-26: 3.3 µg/m³2026-03-27: 7.7 µg/m³2026-03-28: 7.0 µg/m³2026-03-29: 10.5 µg/m³2026-03-30: 14.0 µg/m³2026-03-31: 7.7 µg/m³2026-04-01: 8.3 µg/m³2026-04-02: 3.2 µg/m³2026-04-03: 6.6 µg/m³2026-04-04: 8.0 µg/m³2026-04-05: 9.0 µg/m³2026-04-06: 10.4 µg/m³2026-04-07: 10.6 µg/m³2026-04-08: 6.2 µg/m³2026-04-09: 6.1 µg/m³2026-04-10: 9.1 µg/m³2026-04-11: 14.1 µg/m³2026-04-12: 9.8 µg/m³2026-04-13: 10.5 µg/m³2026-04-14: 11.7 µg/m³2026-04-15: 7.8 µg/m³2026-04-16: 7.2 µg/m³2026-04-17: 7.1 µg/m³2026-04-18: 7.1 µg/m³2026-04-19: 10.4 µg/m³2026-04-20: 9.8 µg/m³2026-04-21: 5.8 µg/m³2026-04-22: 10.0 µg/m³2026-04-23: 10.0 µg/m³2026-04-24: 8.4 µg/m³2026-04-25: 6.9 µg/m³2026-04-26: 8.0 µg/m³2026-04-27: 4.0 µg/m³2026-04-28: 6.9 µg/m³2026-04-29: 13.5 µg/m³2026-04-30: 5.5 µg/m³2026-05-01: 6.1 µg/m³2026-05-02: 5.9 µg/m³2026-05-03: 12.0 µg/m³2026-05-04: 10.6 µg/m³2026-05-05: 6.6 µg/m³2026-05-06: 6.1 µg/m³2026-05-07: 2.1 µg/m³2026-05-08: 4.9 µg/m³2026-05-09: 6.3 µg/m³2026-05-10: 5.9 µg/m³2026-05-11: 5.1 µg/m³2026-05-12: 4.9 µg/m³2026-05-13: 6.3 µg/m³2026-05-14: 11.5 µg/m³2026-05-15: 13.1 µg/m³2026-05-16: 12.5 µg/m³2026-05-17: 15.3 µg/m³2026-05-18: 11.5 µg/m³2026-05-19: 8.2 µg/m³2026-05-20: 3.5 µg/m³2026-05-21: 4.2 µg/m³2026-05-22: 5.7 µg/m³2026-05-23: 8.9 µg/m³2026-05-24: no data2026-05-25: 5.2 µg/m³2026-05-26: 4.3 µg/m³2026-05-27: 5.3 µg/m³2026-05-28: 3.8 µg/m³2026-05-29: 7.6 µg/m³2026-05-30: 6.1 µg/m³2026-05-31: 11.3 µg/m³2026-06-01: 10.6 µg/m³2026-06-02: 5.4 µg/m³2026-06-03: 3.0 µg/m³2026-06-04: 2.9 µg/m³2026-06-05: 4.8 µg/m³2026-06-06: 4.8 µg/m³2026-06-07: 5.9 µg/m³2026-06-08: 3.7 µg/m³2026-06-09: 3.5 µg/m³2026-06-10: 5.3 µg/m³2026-06-11: 4.1 µg/m³2026-06-12: 7.3 µg/m³2026-06-13: 12.6 µg/m³2026-06-14: 9.5 µg/m³2026-06-15: 3.0 µg/m³2026-06-16: 7.3 µg/m³2026-06-17: 4.4 µg/m³2026-06-18: 3.7 µg/m³2026-06-19: 7.5 µg/m³2026-06-20: 6.8 µg/m³2026-06-21: 8.1 µg/m³2026-06-22: 8.2 µg/m³2026-06-23: 4.3 µg/m³2026-06-24: 7.7 µg/m³2026-06-25: 2.8 µg/m³2026-06-26: 4.2 µg/m³2026-06-27: 2.7 µg/m³2026-06-28: 4.6 µg/m³2026-06-29: 5.9 µg/m³2026-06-30: 9.0 µg/m³2026-07-01: 11.0 µg/m³2026-07-02: 6.5 µg/m³2026-07-03: 7.1 µg/m³2026-07-04: 5.8 µg/m³2026-07-05: 5.5 µg/m³2026-07-06: 9.1 µg/m³2026-07-07: 6.8 µg/m³2026-07-08: 5.5 µg/m³2026-07-09: 3.1 µg/m³2026-07-10: 2.3 µg/m³2026-07-11: 2.5 µg/m³2026-07-12: 6.2 µg/m³2026-07-13: 15.0 µg/m³2026-07-14: 11.9 µg/m³2026-07-15: 13.0 µg/m³2026-07-16: 20.3 µg/m³2026-07-17: 16.5 µg/m³2026-07-18: 3.4 µg/m³2026-07-19: 3.1 µg/m³2026-07-20: 5.9 µg/m³2026-07-21: 11.0 µg/m³2026-07-22: 15.4 µg/m³2026-07-23: 21.0 µg/m³2026-07-24: 12.6 µg/m³2026-07-25: 18.8 µg/m³2026-07-26: 7.1 µg/m³2026-07-27: 8.0 µg/m³2026-07-28: 6.3 µg/m³2026-07-29: 8.2 µg/m³2026-07-30: 12.5 µg/m³2026-07-31: 19.8 µg/m³2026-08-01: 18.6 µg/m³2026-08-02: 17.0 µg/m³2026-08-03: 5.3 µg/m³2026-08-04: 7.8 µg/m³2026-08-05: 6.4 µg/m³2026-08-06: 7.6 µg/m³2026-08-07: 4.2 µg/m³2026-08-08: 4.3 µg/m³2026-08-09: 7.3 µg/m³2026-08-10: 8.7 µg/m³2026-08-11: 10.4 µg/m³2026-08-12: 5.5 µg/m³2026-08-13: 4.5 µg/m³2026-08-14: 4.7 µg/m³2026-08-15: 4.9 µg/m³2026-08-16: 4.8 µg/m³2026-08-17: 6.7 µg/m³2026-08-18: 5.7 µg/m³2026-08-19: 5.0 µg/m³2026-08-20: 4.8 µg/m³2026-08-21: 4.3 µg/m³2026-08-22: 4.3 µg/m³2026-08-23: 14.4 µg/m³2026-08-24: 11.4 µg/m³2026-08-25: no data2026-08-26: no data2026-08-27: no data2026-08-28: 5.8 µg/m³2026-08-29: 6.7 µg/m³2026-08-30: 11.1 µg/m³2026-08-31: 6.6 µg/m³2026-09-01: 9.0 µg/m³2026-09-02: 4.6 µg/m³2026-09-03: 4.9 µg/m³2026-09-04: 8.9 µg/m³2026-09-05: 5.6 µg/m³2026-09-06: 2.8 µg/m³2026-09-07: 2.4 µg/m³2026-09-08: 6.2 µg/m³2026-09-09: 7.6 µg/m³2026-09-10: 3.8 µg/m³2026-09-11: 4.4 µg/m³2026-09-12: 4.0 µg/m³2026-09-13: 8.2 µg/m³2026-09-14: 3.7 µg/m³2026-09-15: 3.5 µg/m³2026-09-16: 3.4 µg/m³2026-09-17: 5.4 µg/m³2026-09-18: 5.1 µg/m³2026-09-19: 5.9 µg/m³2026-09-20: 3.4 µg/m³2026-09-21: 1.6 µg/m³2026-09-22: 5.0 µg/m³2026-09-23: 5.5 µg/m³2026-09-24: 7.5 µg/m³2026-09-25: 7.2 µg/m³2026-09-26: 5.7 µg/m³2026-09-27: 13.0 µg/m³2026-09-28: 4.8 µg/m³2026-09-29: 4.6 µg/m³2026-09-30: 4.1 µg/m³2026-10-01: no data
10 of 347 measured days were over the WHO 24-hour guideline (15 µg/m³). One row per month, one square per local day.
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

Last 4 days, hour by hour

15302026-09-30 23:00 UTC: 4.0 µg/m³2026-10-01 00:00 UTC: 2.0 µg/m³2026-10-01 01:00 UTC: 7.0 µg/m³2026-10-01 02:00 UTC: 9.0 µg/m³2026-10-01 03:00 UTC: 6.0 µg/m³2026-10-01 04:00 UTC: 6.0 µg/m³2026-10-01 05:00 UTC: 8.0 µg/m³2026-10-01 06:00 UTC: 10.0 µg/m³2026-10-01 07:00 UTC: 11.0 µg/m³2026-10-01 08:00 UTC: 8.0 µg/m³2026-10-01 09:00 UTC: 9.0 µg/m³2026-10-01 10:00 UTC: 9.0 µg/m³2026-10-01 11:00 UTC: 9.0 µg/m³2026-10-01 12:00 UTC: 8.0 µg/m³2026-10-01 13:00 UTC: 8.0 µg/m³2026-10-01 16:00 UTC: 9.0 µg/m³2026-10-01 17:00 UTC: 9.0 µg/m³2026-10-01 18:00 UTC: 6.0 µg/m³2026-10-01 19:00 UTC: 5.0 µg/m³2026-10-01 20:00 UTC: 5.0 µg/m³2026-10-01 21:00 UTC: 6.0 µg/m³2026-10-01 22:00 UTC: 7.0 µg/m³2026-10-01 23:00 UTC: 6.0 µg/m³2026-10-02 00:00 UTC: 11.0 µg/m³2026-10-02 01:00 UTC: 9.0 µg/m³2026-10-02 02:00 UTC: 6.0 µg/m³2026-10-02 03:00 UTC: 7.0 µg/m³2026-10-02 04:00 UTC: 6.0 µg/m³2026-10-02 05:00 UTC: 8.0 µg/m³Sep 29Sep 30Oct 1Oct 2
Times in UTC. Dashed line: WHO 24-hour guideline (15 µg/m³).

Where it stood each day

Top 10Top 100#1#10#100#1,000#2,835NovDecJanFebMarAprMayJunJulAugSep#2,098
Its rank on each day's world board, #1 being the most polluted city that day. The scale is logarithmic: each step down is ten times as many cities. See it among every city.

2026 against 2025, month by month

15Jan 2025: 6.2 µg/m³Jan 2026: 4.5 µg/m³JanFeb 2025: 4.8 µg/m³Feb 2026: 7.4 µg/m³FebMar 2025: 9.6 µg/m³Mar 2026: 7.1 µg/m³MarApr 2025: 9.5 µg/m³Apr 2026: 8.4 µg/m³AprMay 2025: 8.1 µg/m³May 2026: 7.4 µg/m³MayJun 2025: 9.0 µg/m³Jun 2026: 5.8 µg/m³JunJul 2025: 9.6 µg/m³Jul 2026: 9.7 µg/m³JulAug 2025: 11.0 µg/m³Aug 2026: 7.5 µg/m³AugSep 2025: 8.2 µg/m³Sep 2026: 5.4 µg/m³SepOct 2025: 7.2 µg/m³OctNov 2025: 8.1 µg/m³NovDec 2025: 6.9 µg/m³Dec
Faded bars: 2025. A month shows once it has 10 measured days.

This week against past years

This weekThis week: 6.6 µg/m³6.620252025: 6.7 µg/m³6.720242024: 6.0 µg/m³6.0
Mean PM2.5 for 25 Sept to 1 Oct in each year. Dashed line: WHO 24-hour guideline.

Monitors

StationOperatorType
安房郡鋸南町下佐久間３４５８政府標準利用規約（第2.0版） (Government Standard Terms of Use v2.0)Ministry of the Environment Air Pollutant Wide Area Monitoring SystemReference

The city's value is the median of its reference monitors each hour, when at least a third of them report (three are always enough); low-cost sensors are listed but not counted when reference monitors exist. Data via OpenAQ; licences as listed. How we rank. Embed this on your site.

Use this page

SmogRank, PM2.5 daily means, Minamibōsō, Japan, 2 Oct 2025 – 30 Sep 2026, smogrank.com/jp/minamiboso (accessed 2 Oct 2026).

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Other cities in Japan

30-day averages, US AQI. All of Japan.

Updated 2026-10-02 07:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.