SmogRank / History / City race
Cities in South Korea, worst air first, day by day
Each measured city's average over the 30 days to every day since January 2024, worst first. Find your own city to follow it through the race, or keep to one country.
The worst cities in South Korea for PM2.5 over the 30 days to 1 Sep 2026: Jeongeup 15.6 µg/m³, Seonghwan 15.1 µg/m³ and Tangjin 14.9 µg/m³.
- 1JeongeupJeollabuk-do15.6
- 2SeonghwanChungcheongnam-do15.1
- 3TangjinChungcheongnam-do14.9
- 4YesanChungcheongnam-do13.8
- 5Gimpo-siGyeonggi-do13.7
- 6IncheonIncheon13.6
- 7GwangmyeongGyeonggi-do13.4
- 8PyeongtaekGyeonggi-do12.8
- 9AsanChungcheongnam-do12.6
- 10Ganghwa-gunIncheon12.6
- 11ChungjuNorth Chungcheong12.4
- 12YeojuGyeonggi-do12.2
- 13WanjuJeollabuk-do12.2
- 14Chinch'ŏnNorth Chungcheong12.2
- 15Ansan-siGyeonggi-do12.1
- 16Yongsan-dongSeoul12.1
- 17GunsanJeollabuk-do12.0
- 18KoesanNorth Chungcheong12.0
- 19HongseongChungcheongnam-do12.0
- 20UlsanUlsan11.9
+ 102 more cities, 11.9 µg/m³ and below
Not counted on this day, too few days measured: Pubal since 1 Sep 2026, Okcheon since 31 Aug 2026, Kimje since 30 Aug 2026 and Hadong since 30 Jul 2026.
Cities counted each day
A city's number is its average over the 30 days, shown only when 21 of them were measured (5 of 7 on the 7-day race), the same minimum as the 30- and 7-day boards. A city whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air. Some large countries are thin or missing because their monitors' licences don't allow reuse. How we rank.
Not covered: the government monitoring networks of China and Turkey, which publish only on their own websites; we are building the readers for them. Most cities there are missing from this board, not clean. Why.