Stay updated with real-time air quality in Merrillville, Indiana 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)
27
Good
Merrillville, Indiana
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
4.21 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
18.86 μg/m³
0
55
155
255
425
605+
29.03 ppb
0
55
71
86
201
201+
1.35 ppb
0
36
76
186
605
1005+
10.69 ppb
0
54
101
361
1250
2050+
0.21 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
Low
Merrillville, Indiana
Merrillville, Indiana
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AQI 26
Good
4.38μg/m³
PM2.5
20.42μg/m³
PM10
28.48ppb
O3
1.40ppb
SO2
9.23ppb
NO2
0.21ppm
CO
AQI 27
Good
4.44μg/m³
PM2.5
19.63μg/m³
PM10
29.07ppb
O3
0.74ppb
SO2
4.38ppb
NO2
0.21ppm
CO
AQI 33
Good
5.86μg/m³
PM2.5
25.23μg/m³
PM10
24.68ppb
O3
1.63ppb
SO2
9.08ppb
NO2
0.20ppm
CO
AQI 33
Good
5.88μg/m³
PM2.5
25.32μg/m³
PM10
24.45ppb
O3
1.74ppb
SO2
9.53ppb
NO2
0.20ppm
CO
AQI 27
Good
4.21μg/m³
PM2.5
18.93μg/m³
PM10
28.66ppb
O3
1.76ppb
SO2
9.86ppb
NO2
0.20ppm
CO
AQI 33
Good
5.93μg/m³
PM2.5
25.47μg/m³
PM10
24.77ppb
O3
1.74ppb
SO2
9.62ppb
NO2
0.20ppm
CO
Air quality measurements for Indiana, USA meet strict US EPA standards. These measurements are collected from reliable sources, including satellites and ground-based monitoring systems. Advanced algorithms and machine learning techniques are applied to the data, factoring in variables such as traffic and population density, to ensure precision and reliability.
Source: Ambee Data Sources
Air quality data for Merrillville, Indiana is updated on an hourly basis.
The worst air quality in Merrillville, Indiana was recorded at 10:00:00 on 2026-01-24.
The best air quality in Merrillville, Indiana was recorded at 12:00:00 on 2026-01-25.
The real-time air quality index in Merrillville, Indiana is 27, currently categorized as Good.
The most common pollutant in Merrillville, Indiana is O3.
If the air quality in Merrillville, Indiana is poor, limit outdoor activities and use a mask to safeguard your health.
The measured PM2.5 levels in Merrillville, Indiana at present are 4.215 μg/m3.
The current PM10 levels in Merrillville, Indiana are 18.857 μg/m3.
The current carbon monoxide (CO) level in Merrillville, Indiana is 0.212 ppm.
The current sulfur dioxide (SO2) levels in Merrillville, Indiana are 1.352 ppb.
The current ozone (O3) levels at Merrillville, Indiana is 29.029 ppm.
The current nitrogen dioxide (NO2) levels at Merrillville, Indiana is 10.687 ppb.
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