Air quality in Honjo, Japan today

Mr. Duck’s Air Quality Score

Good air today for Honjo, Japan

⚠️ This website is currently under active development. Some data may be incomplete or temporarily inaccurate. For health-critical decisions, please verify information through official government or environmental sources.

Categories follow US EPA AQI breakpoints for PM (estimate from latest valid measurements; this project does not compute EPA NowCast/24-hour AQI yet).

This friendly indicator summarizes the latest city readings. For health guidance, please see: EPA AirNow or WHO.

Air quality today

The air quality in Honjo is currently classified as Good. The main pollutant identified is PM2.5, with a measured concentration of 8.0 µg/m³ based on nine valid observations reported through OpenAQ.

Overall conditions meet the criteria for the Good category, reflecting low levels of fine particulate matter at the time of measurement. This page is informational; for health guidance, use official sources such as EPA AirNow or WHO.

Latest sensor values

PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).

What the data includes

The Honjo dataset contains five measured pollutants – nitrogen monoxide (NO), nitrogen dioxide (NO₂), total nitrogen oxides (NOX), fine particulate matter (PM2.5) and sulfur dioxide (SO₂). The data come from nine individual rows that are grouped into two monitoring stations, giving a modest spatial coverage across the city. All of the reported values were last updated on 2026-02-10 at 22:00 UTC, which means the information is fresh within the past three days for every pollutant.

For the nitrogen compounds the observed concentrations are very low and tightly clustered. NO ranges from 0.000 ppm to a maximum of 0.001 ppm with a median of 0.0005 ppm; NO₂ varies between 0.008 ppm and 0.009 ppm, median 0.0085 ppm; and NOX spans 0.008 ppm to 0.010 ppm, median 0.009 ppm. The narrow spread (the 10th‑percentile values are only slightly above the minima and the 90th‑percentile values are just below the maxima) indicates little variability among the recent readings at the two sites.

PM2.5 is reported as a single value of 8.0 µg/m³ for both stations, with no observed range or deviation in the current batch of rows. SO₂ shows a uniform reading of 0.0 ppm from one location (本庄市日の出4-2-45), again without any variation.

Overall the dataset provides recent, consistent measurements but is limited to two locations and nine rows, so it captures only a snapshot of city‑wide air quality. Conditions can differ in other neighborhoods or at times outside the latest update window.

Learn more about sources and filtering: About the data.

Trusted references: WHO (Air pollution) · US EPA AirNow · European Environment Agency (Air)

Latest sensor values (bars)

PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).

Data notes

The data shown reflects nine valid measurements and was refreshed recently, with the latest update recorded on 2026‑02‑10 at 22:00 UTC, meaning it is updated within three days. These readings provide a snapshot of Honjo’s current air quality, but conditions can differ across neighborhoods and change throughout the day, so local variations may exist.

OpenAQ station rows