Stay updated with real-time air quality in Crystal Lake, 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)
41
Good
Crystal Lake, Illinois
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
5.30 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
23.50 μg/m³
0
55
155
255
425
605+
44.37 ppb
0
55
71
86
201
201+
0.71 ppb
0
36
76
186
605
1005+
5.77 ppb
0
54
101
361
1250
2050+
0.25 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
Crystal Lake, Illinois
Scroll To Air Quality MapLoading...
AQI 42
Good
5.20μg/m³
PM2.5
23.00μg/m³
PM10
45.00ppb
O3
0.71ppb
SO2
5.97ppb
NO2
0.25ppm
CO
AQI 40
Good
5.43μg/m³
PM2.5
24.15μg/m³
PM10
43.39ppb
O3
0.72ppb
SO2
5.20ppb
NO2
0.25ppm
CO
AQI 40
Good
5.44μg/m³
PM2.5
24.21μg/m³
PM10
43.38ppb
O3
0.72ppb
SO2
5.19ppb
NO2
0.25ppm
CO
AQI 43
Good
5.58μg/m³
PM2.5
24.19μg/m³
PM10
45.63ppb
O3
0.68ppb
SO2
3.31ppb
NO2
0.25ppm
CO
AQI 42
Good
5.49μg/m³
PM2.5
26.86μg/m³
PM10
45.28ppb
O3
0.69ppb
SO2
3.38ppb
NO2
0.24ppm
CO
AQI 43
Good
5.50μg/m³
PM2.5
24.33μg/m³
PM10
45.56ppb
O3
0.67ppb
SO2
3.41ppb
NO2
0.24ppm
CO
Air quality data and pollutant measurements for Illinois, USA adhere to strict US EPA standards. The data is collected from multiple reliable sources, including satellites and ground-based monitoring stations. This data is further analyzed and enhanced using machine learning and advanced algorithms that factor in elements such as traffic and population density, ensuring accurate and reliable results.
Source: Ambee Data Sources
The air quality for Crystal Lake, Illinois is updated every hour.
The worst air quality in Crystal Lake, Illinois in the last 24 hours was observed at 10:00:00 on 2026-03-09.
In the last 24 hrs, the best air quality in Crystal Lake, Illinois was observed at 03:00:00 on 2026-03-09.
The current air quality in Crystal Lake, Illinois is 41, categorized as Good based on real-time data.
The most common pollutant in Crystal Lake, Illinois is O3.
If the air quality in Crystal Lake, Illinois is poor, consider staying indoors and wearing a mask to protect yourself.
The current PM2.5 concentration at Crystal Lake, Illinois is 5.302 μg/m3.
The current PM10 concentration at Crystal Lake, Illinois is 23.498 μg/m3.
The current carbon monoxide (CO) concentration at Crystal Lake, Illinois is 0.249 ppm.
The current sulfur dioxide (SO2) concentration at Crystal Lake, Illinois is 0.711 ppb.
The current ozone (O3) concentration at Crystal Lake, Illinois is 44.368 ppm.
The current nitrogen dioxide (NO2) concentration at Crystal Lake, Illinois is 5.767 ppb.
All Rights Reserved © Ambee Inc. 2025