Daejeon, Daejeon, South Korea Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
September Air Quality Analysis
Daejeon, Daejeon, South Korea
AQI Trends: Highest and Lowest
Same Day Analysis (4th September ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 1st highest AQI at 42 of Good air quality on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 4th Sep - 5th Sep 2025
Daejeon, Daejeon, South Korea
5 AM4th Sep 2025
7 PM
4 AM5th Sep 2025
49AQI
26AQI
49AQI
28AQI
In the last 24 hours,
Daejeon's AQI reached its highest point of 49 at 5 AM during the Night, while the lowest point, 26, was recorded at 3 PM during the Day between 4th Sep and 5th Sep 2025.
Day & Night AQI Trend : Aug - Sep 2025
Daejeon, Daejeon, South Korea
25°C22/29°C
25°C21/31°C
24°C19/30°C
22°C20/24°C
24°C19/29°C
22°C19/27°C
22°C17/27°C
25°C21/31°C
25°C21/29°C
26°C21/31°C
26°C21/32°C
25°C20/32°C
26°C21/32°C
26°C21/31°C
26°C21/33°C
27°C22/34°C
27°C23/33°C
27°C21/33°C
27°C22/34°C
27°C22/33°C
25°C22/30°C
25°C20/32°C
25°C20/32°C
26°C22/32°C
26°C23/33°C
26°C21/33°C
26°C21/32°C
23°C21/29°C
24°C18/32°C
23°C20/25°C
--°C/°C
49AQI
40AQI
49AQI
44AQI
2025 Days Vs Air Quality
Daejeon, Daejeon, South Korea
36%
89
61%
151
3%
7
Total number of days with different AQI categories in last 248 days in 2025 (117 days remaining)
Under WHO’s Safe Air Quality Limits: 36%
Health Risk Level:
High
In 2025, 36% of 248 days were within WHO’s safe air quality limits. The risk of health issues is High, with respiratory problems, heart disease, skin issues, and stress being more common, particularly among children and the elderly.
Annual Air Quality Insights
Daejeon, Daejeon, South Korea
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
62AQI
60AQI
54AQI
54AQI
59AQI
76AQI
53AQI
61AQI
41AQI
55AQI
58AQI
69AQI
76AQI
81AQI
55AQI
61AQI
82AQI
79AQI
73AQI
95AQI
127AQI
130AQI
117AQI
107AQI
81AQI
57AQI
64AQI
49AQI
57AQI
57AQI
71AQI
83AQI
89AQI
60AQI
52AQI
47AQI
51AQI
50AQI
45AQI
50AQI
57AQI
69AQI
65AQI
50AQI
71AQI
56AQI
96AQI
53AQI
58AQI
47AQI
54AQI
50AQI
57AQI
53AQI
52AQI
53AQI
75AQI
61AQI
64AQI
74AQI
68AQI
49AQI
44AQI
36AQI
62AQI
73AQI
70AQI
81AQI
79AQI
88AQI
82AQI
78AQI
73AQI
46AQI
62AQI
59AQI
72AQI
79AQI
89AQI
93AQI
101AQI
98AQI
103AQI
122AQI
82AQI
87AQI
68AQI
52AQI
51AQI
60AQI
71AQI
76AQI
77AQI
79AQI
66AQI
64AQI
64AQI
73AQI
65AQI
75AQI
73AQI
63AQI
58AQI
45AQI
53AQI
61AQI
64AQI
77AQI
53AQI
60AQI
46AQI
41AQI
40AQI
56AQI
59AQI
48AQI
41AQI
52AQI
59AQI
56AQI
50AQI
49AQI
48AQI
46AQI
47AQI
45AQI
50AQI
65AQI
42AQI
46AQI
62AQI
64AQI
69AQI
70AQI
53AQI
46AQI
46AQI
56AQI
58AQI
44AQI
43AQI
54AQI
56AQI
45AQI
44AQI
58AQI
70AQI
71AQI
76AQI
66AQI
74AQI
81AQI
91AQI
78AQI
60AQI
56AQI
61AQI
64AQI
62AQI
60AQI
57AQI
52AQI
56AQI
62AQI
42AQI
51AQI
55AQI
60AQI
61AQI
63AQI
48AQI
42AQI
33AQI
46AQI
45AQI
38AQI
49AQI
56AQI
58AQI
46AQI
45AQI
43AQI
41AQI
51AQI
51AQI
47AQI
50AQI
57AQI
58AQI
51AQI
49AQI
51AQI
51AQI
59AQI
53AQI
42AQI
51AQI
41AQI
43AQI
34AQI
42AQI
40AQI
35AQI
45AQI
51AQI
50AQI
43AQI
38AQI
49AQI
49AQI
47AQI
51AQI
56AQI
63AQI
61AQI
51AQI
51AQI
49AQI
48AQI
48AQI
53AQI
46AQI
51AQI
43AQI
39AQI
39AQI
39AQI
38AQI
40AQI
50AQI
43AQI
45AQI
47AQI
46AQI
48AQI
51AQI
48AQI
43AQI
48AQI
53AQI
45AQI
44AQI
49AQI
40AQI
45AQI
48AQI
42AQI
72AQI
60AQI
74AQI
61AQI
55AQI
56AQI
47AQI
48AQI
44AQI
No. of days
202559AQI
Highest AQI recorded in
March74AQI
Lowest AQI recorded in
September44AQI
202454AQI
Highest AQI recorded in
January67AQI
Lowest AQI recorded in
July34AQI
202363AQI
Highest AQI recorded in
February88AQI
Lowest AQI recorded in
September44AQI
202263AQI
Highest AQI recorded in
February80AQI
Lowest AQI recorded in
August35AQI
202160AQI
Highest AQI recorded in
March81AQI
Lowest AQI recorded in
September38AQI
202057AQI
Highest AQI recorded in
December71AQI
Lowest AQI recorded in
July38AQI
Most & Least Polluted Years Over the Last 6 Years
Daejeon's annual 2025 AQI (59) shows an average percentage change of -0.7% (improved AQI) compared to previous years: 2020 (57), 2021 (60), 2022 (63), 2023 (63), 2024 (54).