Is the air quality good in Seoul?
On January 16, 2026, at 4:45 AM PT, air quality in Seoul, South Korea is unhealthy, with an Air Quality Index of 170.
The elevated pollution levels are driven by an influx of fine dust from outside Korea (1), compounded by stagnant winter weather conditions that allow pollutants to accumulate locally.
Air quality in this range may begin to affect both the general public and sensitive groups such as children, older adults, pregnant people, and individuals with heart or lung conditions. It is recommended to limit prolonged outdoor activities, consider wearing a mask when outside, and use indoor air purifiers.
Air quality is dynamic and, like the weather, can change frequently, Seoul ranked 9th among the most polluted major cities in the world on Friday morning (local time).
The affected region extended across north-west South Korea, impacting nearby cities such as Incheon, Suwon, Sejong, Gunsan, Seosan, Cheongju, Daejeon and Cheonan.
Click here for a real-time air quality map of Seoul.
While the air quality today is poor, it’s worth noting that the average PM2.5 concentration in 2024 for Seoul was 17.5 µg/m3, corresponding to an AQI of 62 (“moderate”), and was 3.5 times the WHO annual guideline of 5 µg/m3.
Seoul, South Korea ranked as the 9th most polluted major city on Jan 16, 2026 at 4:45 AM PT. Source: IQAir.
When will air quality improve in Seoul?
Air quality is forecasted to improve by Saturday, returning to the moderate range.
Hourly air quality forecast for Seoul, South Korea on Jan 16, 2026. Source: IQAir.
However, over the past 30 days, air quality in Seoul has remained mostly in the moderate range, with today’s conditions marking a temporary spike into unhealthy levels, reflecting short-term pollution buildup rather than a sustained deterioration.
Daily air quality trends in Seoul, South Korea, over the past 30 days. Source: IQAir.
Air quality map of Seoul, South Korea on Jan 16, 2026. Source: IQAir.
What is causing poor air quality in Seoul?
A combination of international transport and local emissions is driving the current decline in air quality.
Fine dust and yellow dust are being carried into Korea by winds from the Gobi Desert and Inner Mongolia (2). Westerly and southwesterly winds are also transporting additional pollutants from China into the region (3).
At the local level, winter weather conditions are limiting air movement, allowing pollutants to build up near the ground rather than dispersing. Emissions from traffic, industrial activity, and fuel combustion contribute to higher PM2.5 levels, while the presence of heavy metals increases the overall toxicity of the pollution (4).
How can I protect myself from poor air quality?
- Get a free air quality app for real-time air quality alerts and forecasts.
- Shut doors and windows and set the HVAC to recirculate mode.
- Contribute to your community’s outdoor air quality data.
- Stay indoors when air quality is poor; if you do need to go outdoors, wear a KN95/FFP2 mask.
- Run a high-performance air purifier to filter particles, gases, and other pollutants.
