Champaign, Illinois, United States 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
Champaign, Illinois, United States
AQI Trends: Highest and Lowest
Same Day Analysis (26th September ):
On this day, AQI across the 1 years varied significantly: 2025 ranks 1st highest AQI at 27 of Good air quality on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 27th Sep - 28th Sep 2025
Champaign, Illinois, United States
6 AM27th Sep 2025
7 PM
5 AM28th Sep 2025
35AQI
29AQI
44AQI
33AQI
In the last 24 hours,
Champaign's AQI reached its highest point of 44 at 11 PM during the Night, while the lowest point, undefined, was recorded at 5 AM during the Night between 27th Sep and 28th Sep 2025.
Day & Night AQI Trend : Aug - Sep 2025
Champaign, Illinois, United States
19°C11/27°C
19°C12/28°C
19°C10/26°C
19°C9/28°C
20°C9/30°C
21°C12/30°C
16°C8/23°C
17°C10/23°C
16°C8/24°C
14°C5/23°C
15°C5/25°C
16°C5/26°C
21°C11/31°C
22°C12/32°C
22°C11/33°C
24°C15/35°C
25°C16/34°C
24°C15/34°C
22°C14/33°C
22°C11/33°C
24°C12/34°C
23°C15/30°C
24°C20/30°C
24°C17/32°C
22°C19/25°C
22°C17/30°C
21°C17/25°C
19°C14/26°C
20°C9/31°C
22°C12/33°C
--°C/°C
42AQI
42AQI
42AQI
42AQI
2025 Days Vs Air Quality
Champaign, Illinois, United States
76%
140
23%
43
0.5%
1
Total number of days with different AQI categories in last 271 days in 2025 (94 days remaining)
Under WHO’s Safe Air Quality Limits: 76%
Health Risk Level:
Low
In 2025, 76% of 271 days were within WHO’s safe air quality limits. The risk of health issues is Low, but the long-term effects, especially on vulnerable individuals, remain uncertain.
Annual Air Quality Insights
Champaign, Illinois, United States
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
33AQI
34AQI
38AQI
28AQI
17AQI
25AQI
24AQI
21AQI
29AQI
19AQI
20AQI
23AQI
17AQI
22AQI
35AQI
39AQI
33AQI
30AQI
29AQI
20AQI
23AQI
31AQI
47AQI
42AQI
34AQI
19AQI
22AQI
24AQI
29AQI
31AQI
22AQI
18AQI
25AQI
29AQI
20AQI
22AQI
20AQI
22AQI
16AQI
21AQI
29AQI
21AQI
24AQI
25AQI
28AQI
23AQI
26AQI
21AQI
24AQI
43AQI
33AQI
21AQI
17AQI
19AQI
22AQI
16AQI
16AQI
18AQI
19AQI
22AQI
20AQI
20AQI
25AQI
40AQI
34AQI
50AQI
33AQI
41AQI
57AQI
50AQI
53AQI
62AQI
69AQI
65AQI
61AQI
57AQI
65AQI
85AQI
76AQI
50AQI
46AQI
43AQI
30AQI
38AQI
26AQI
34AQI
40AQI
44AQI
57AQI
54AQI
49AQI
50AQI
40AQI
27AQI
34AQI
26AQI
28AQI
44AQI
49AQI
55AQI
72AQI
59AQI
54AQI
68AQI
47AQI
41AQI
45AQI
36AQI
41AQI
41AQI
50AQI
34AQI
26AQI
24AQI
29AQI
28AQI
33AQI
60AQI
61AQI
55AQI
44AQI
36AQI
26AQI
27AQI
30AQI
37AQI
52AQI
109AQI
85AQI
55AQI
51AQI
56AQI
55AQI
47AQI
54AQI
54AQI
50AQI
51AQI
41AQI
46AQI
58AQI
60AQI
53AQI
45AQI
46AQI
40AQI
22AQI
20AQI
30AQI
35AQI
25AQI
20AQI
26AQI
31AQI
34AQI
30AQI
27AQI
30AQI
30AQI
31AQI
37AQI
58AQI
52AQI
25AQI
29AQI
25AQI
30AQI
44AQI
53AQI
52AQI
57AQI
59AQI
53AQI
50AQI
54AQI
57AQI
58AQI
59AQI
47AQI
35AQI
38AQI
42AQI
25AQI
27AQI
30AQI
27AQI
24AQI
49AQI
43AQI
45AQI
43AQI
No. of days
202538AQI
Highest AQI recorded in
June49AQI
Lowest AQI recorded in
May24AQI
Most & Least Polluted Years Over the Last 1 Years
Champaign's annual 2025 AQI (38) shows an average percentage change of NaN% (improved AQI) compared to previous years: .