Air quality in Matsuyama, Japan today

Mr. Duck’s Air Quality Score

Moderate air today for Matsuyama, 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 Matsuyama is currently rated as Moderate. The primary pollutant identified is PM2.5 (fine particles). Measurements show a PM2.5 concentration of 26.0 µg/m³, based on 21 valid observations collected via OpenAQ.

This assessment reflects the latest available data for the city. 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

Matsuyama’s OpenAQ feed includes six measured pollutants – carbon monoxide (CO), nitrogen oxide (NO), nitrogen dioxide (NO₂), total nitrogen oxides (NOX), fine particulate matter (PM2.5) and sulfur dioxide (SO₂). The data come from five monitoring stations, each providing a single recent row of observations that were last refreshed on 2026-02-10 22:00 UTC, well within the three‑day freshness window used by the platform.

The CO record comes from one station in 朝生田町 and shows a uniform value of 0.4 ppm, with no variation across its minimum, median and maximum because only one recent measurement is available. The other four stations report NO, NO₂, NOX and SO₂ at the same site in 北斎院町７１２. For these gases the observed ranges are narrow: NO varies from 0.001 to 0.01 ppm (median 0.001 ppm), NO₂ from 0.005 to 0.018 ppm (median 0.015 ppm) and NOX from 0.006 to 0.028 ppm (median 0.016 ppm). SO₂ is essentially absent, with values between 0 and 0.001 ppm and a median of zero.

PM2.5 measurements at the same 北斎院町 location span 8.0 to 26.0 µg/m³, with a median of 21 µg/m³; the 10th‑percentile is 10.4 µg/m³ and the 90th‑percentile reaches 24.8 µg/m³, indicating modest day‑to‑day variability within this limited sample.

Overall the dataset provides recent snapshots for all six pollutants but is unevenly distributed: CO is captured at a single site, while the other five pollutants share one location. Because each station contributes only one fresh row, the picture reflects conditions at specific points in time and space rather than citywide averages, and actual air quality may differ across neighborhoods or later periods.

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 for Matsuyama reflects 21 valid measurements and is marked as Updated within 3 days, with the latest values recorded at 2026‑02‑10T22:00:00+00:00. This snapshot provides a recent overview of ambient air quality across the city, but conditions can differ by neighborhood and change throughout the day, so local variations may not be captured in these figures.

OpenAQ station rows