Stay updated with real-time air quality in Markham, 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)
66
Moderate
Markham, Illinois
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
16.96 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
75.07 μg/m³
0
55
155
255
425
605+
26.99 ppb
0
55
71
86
201
201+
2.02 ppb
0
36
76
186
605
1005+
1.76 ppb
0
54
101
361
1250
2050+
0.22 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
Low
Markham, Illinois
Markham, Illinois
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AQI 67
Moderate
18.25μg/m³
PM2.5
80.38μg/m³
PM10
30.44ppb
O3
3.00ppb
SO2
3.30ppb
NO2
0.20ppm
CO
AQI 69
Moderate
18.66μg/m³
PM2.5
85.74μg/m³
PM10
28.61ppb
O3
2.69ppb
SO2
3.29ppb
NO2
0.20ppm
CO
AQI 66
Moderate
16.81μg/m³
PM2.5
74.23μg/m³
PM10
31.76ppb
O3
2.59ppb
SO2
3.30ppb
NO2
0.20ppm
CO
AQI 66
Moderate
16.67μg/m³
PM2.5
73.69μg/m³
PM10
31.43ppb
O3
2.61ppb
SO2
3.30ppb
NO2
0.20ppm
CO
AQI 67
Moderate
18.35μg/m³
PM2.5
80.86μg/m³
PM10
30.31ppb
O3
3.05ppb
SO2
3.30ppb
NO2
0.20ppm
CO
AQI 66
Moderate
17.47μg/m³
PM2.5
77.69μg/m³
PM10
28.59ppb
O3
2.87ppb
SO2
3.29ppb
NO2
0.20ppm
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 Markham, Illinois is updated every hour for accuracy.
In the past 24 hours, the air quality in Markham, Illinois was at its worst at 07:00:00 on 2026-08-23.
In the last 24 hours, the best air quality in Markham, Illinois was observed at 03:00:00 on 2026-08-23.
As of now, the AQI in Markham, Illinois is 66, indicating Moderate conditions.
Markham, Illinois air has the highest levels of PM2.5.
Poor air quality in Markham, Illinois means it's advisable to stay indoors and wear a mask for your protection.
PM2.5 levels in Markham, Illinois are currently 16.963 μg/m3.
The PM10 concentration in Markham, Illinois is 75.067 μg/m3 at the moment.
The current carbon monoxide (CO) concentration in Markham, Illinois is 0.223 ppm.
Currently, Markham, Illinois has a sulfur dioxide (SO2) concentration of 2.022 ppb.
The current ozone (O3) level in Markham, Illinois at the moment is 26.987 ppm.
Nitrogen dioxide (NO2) level in Markham, Illinois at the moment is 1.765 ppb.
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