Stay updated with real-time air quality in Fremont, California 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)
37
Good
Fremont, California
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
5.04 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
26.16 μg/m³
0
55
155
255
425
605+
40.48 ppb
0
55
71
86
201
201+
0.48 ppb
0
36
76
186
605
1005+
4.46 ppb
0
54
101
361
1250
2050+
0.28 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
Moderate
Fremont, California
Fremont, California
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AQI 42
Good
5.50μg/m³
PM2.5
36.94μg/m³
PM10
45.28ppb
O3
0.50ppb
SO2
3.68ppb
NO2
0.26ppm
CO
AQI 40
Good
6.28μg/m³
PM2.5
29.11μg/m³
PM10
42.86ppb
O3
0.51ppb
SO2
3.74ppb
NO2
0.26ppm
CO
AQI 49
Good
8.52μg/m³
PM2.5
38.63μg/m³
PM10
53.37ppb
O3
0.52ppb
SO2
5.95ppb
NO2
0.28ppm
CO
AQI 39
Good
6.13μg/m³
PM2.5
28.52μg/m³
PM10
42.22ppb
O3
0.49ppb
SO2
3.61ppb
NO2
0.27ppm
CO
AQI 39
Good
6.13μg/m³
PM2.5
28.52μg/m³
PM10
42.22ppb
O3
0.49ppb
SO2
3.61ppb
NO2
0.27ppm
CO
AQI 45
Good
8.43μg/m³
PM2.5
37.23μg/m³
PM10
48.83ppb
O3
0.54ppb
SO2
3.46ppb
NO2
0.26ppm
CO
Air quality data and pollutant measurements for California, 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 Fremont, California is updated every hour.
The worst air quality in Fremont, California in the last 24 hours was observed at 02:00:00 on 2026-06-12.
In the last 24 hrs, the best air quality in Fremont, California was observed at 01:00:00 on 2026-06-12.
The current air quality in Fremont, California is 40, categorized as Good based on real-time data.
The most common pollutant in Fremont, California is O3.
If the air quality in Fremont, California is poor, consider staying indoors and wearing a mask to protect yourself.
The current PM2.5 concentration at Fremont, California is 5.923 μg/m3.
The current PM10 concentration at Fremont, California is 25.892 μg/m3.
The current carbon monoxide (CO) concentration at Fremont, California is 0.252 ppm.
The current sulfur dioxide (SO2) concentration at Fremont, California is 0.494 ppb.
The current ozone (O3) concentration at Fremont, California is 42.849 ppm.
The current nitrogen dioxide (NO2) concentration at Fremont, California is 3.695 ppb.
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