Stay updated with real-time air quality in Belvidere, Illinois featuring accurate data on AQI, PM2.5, PM10, O3, NO2, SO2, and CO levels. Use our interactive map and detailed forecasts to monitor pollution trends, manage health risks, and plan your daily activities with confidence.
Live AQI (Air Quality Index)
49
Good
Belvidere, Illinois
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
9.20 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
36.79 μg/m³
0
55
155
255
425
605+
46.12 ppb
0
55
71
86
201
201+
1.04 ppb
0
36
76
186
605
1005+
6.66 ppb
0
54
101
361
1250
2050+
0.22 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
High
Belvidere, Illinois
Belvidere, Illinois
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AQI 49
Good
8.62μg/m³
PM2.5
36.43μg/m³
PM10
43.08ppb
O3
1.01ppb
SO2
3.57ppb
NO2
0.21ppm
CO
AQI 49
Good
8.62μg/m³
PM2.5
36.42μg/m³
PM10
43.02ppb
O3
1.02ppb
SO2
3.57ppb
NO2
0.21ppm
CO
AQI 49
Good
8.50μg/m³
PM2.5
36.99μg/m³
PM10
45.13ppb
O3
1.04ppb
SO2
3.55ppb
NO2
0.21ppm
CO
AQI 49
Good
8.64μg/m³
PM2.5
36.34μg/m³
PM10
43.40ppb
O3
0.99ppb
SO2
3.71ppb
NO2
0.21ppm
CO
AQI 49
Good
8.70μg/m³
PM2.5
36.56μg/m³
PM10
43.06ppb
O3
0.97ppb
SO2
3.63ppb
NO2
0.21ppm
CO
AQI 52
Moderate
9.97μg/m³
PM2.5
38.02μg/m³
PM10
48.47ppb
O3
0.88ppb
SO2
11.72ppb
NO2
0.23ppm
CO
Air quality and pollutant data for Illinois, USA are sourced from ground-based monitors and satellites, adhering to US EPA standards. Machine learning and advanced algorithms enhance the data by incorporating local variables like traffic and population density, ensuring high accuracy and dependability.
Source: Ambee Data Sources
The air quality information for Belvidere, Illinois is updated every hour for accuracy.
In the past 24 hours, the air quality in Belvidere, Illinois was at its worst at 09:00:00 on 2026-04-23.
In the last 24 hours, the best air quality in Belvidere, Illinois was observed at 06:00:00 on 2026-04-23.
As of now, the AQI in Belvidere, Illinois is 49, indicating Good conditions.
Belvidere, Illinois air has the highest levels of PM2.5.
Poor air quality in Belvidere, Illinois means it's advisable to stay indoors and wear a mask for your protection.
PM2.5 levels in Belvidere, Illinois are currently 9.204 μg/m3.
The PM10 concentration in Belvidere, Illinois is 36.787 μg/m3 at the moment.
The current carbon monoxide (CO) concentration in Belvidere, Illinois is 0.219 ppm.
Currently, Belvidere, Illinois has a sulfur dioxide (SO2) concentration of 1.043 ppb.
The current ozone (O3) level in Belvidere, Illinois at the moment is 46.116 ppm.
Nitrogen dioxide (NO2) level in Belvidere, Illinois at the moment is 6.663 ppb.
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