Air quality in Seoul, South Korea today

Mr. Duck’s Air Quality Score

Unhealthy air today for Seoul, South Korea

⚠️ 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 today in Seoul is classified as Unhealthy. The primary pollutant identified is PM2.5 (fine particles). Measurements show a PM2.5 concentration of 60.0 µg/m³ and a PM10 level of 84.0 µg/m³, based on 234 valid observations.

Data are shown via OpenAQ. 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

Seoul’s OpenAQ feed contains data from 292 measurement rows collected at 43 monitoring sites. For the core air‑quality gases and particles—carbon monoxide (CO), nitrogen dioxide (NO₂), ozone (O₃), sulfur dioxide (SO₂), PM1, PM2.5, PM10—as well as meteorological variables (relative humidity and temperature) the dataset provides recent values for most pollutants: CO, NO₂, O₃, PM2.5, PM10 and SO₂ all have a “last updated” timestamp of 2026‑02‑10 18:00 UTC, meaning they were recorded within the past week. The humidity and temperature readings are older, with their latest entry on 2026‑01‑17 07:00 UTC, which falls into the 30‑day freshness window.

Across the pollutants, the observed ranges illustrate considerable variability. PM2.5 values span from a low of 3.7 µg/m³ to an extreme high of 9 999 µg/m³, with a median of 45 µg/m³ and a 10th‑percentile of 17 µg/m³, indicating that most recent measurements sit in the mid‑range but occasional spikes are recorded. CO concentrations range between 0.25 ppm and 1.07 ppm (median 0.65 ppm), while NO₂ varies from 0.0082 ppm to 0.061 ppm (median 0.0462 ppm). Ozone shows a broader spread, from 0.0011 ppm up to 0.0718 ppm, with the median at just 0.0033 ppm. PM10 readings also cover a wide interval, 22 µg/m³ to 9 999 µg/m³ (median 61 µg/m³). Relative humidity recorded at one site ranges from about 26 % to 63 %, with a median near 45 %.

The dataset is unevenly balanced: while particulate matter and gas pollutants have strong recent coverage across many stations, the meteorological variables are represented by only two rows each and are older. Consequently, city‑wide conditions can differ noticeably between neighborhoods and over time, especially where data are sparse or not refreshed within the last week.

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 dataset for Seoul includes 234 valid measurements and is refreshed regularly, with the latest update recorded on 2026‑02‑10T18:00:00+00:00 and labeled as Updated within 3 days. While this information reflects recent monitoring across the city, air quality can differ by specific neighborhoods and at different times of day, so conditions may vary locally from the presented snapshot.

OpenAQ station rows