Stay updated with real-time air quality in Castro Valley, 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)
33
Good
Castro Valley, California
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
6.45 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
32.08 μg/m³
0
55
155
255
425
605+
34.66 ppb
0
55
71
86
201
201+
0.71 ppb
0
36
76
186
605
1005+
4.69 ppb
0
54
101
361
1250
2050+
0.36 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
Low
Castro Valley, California
Castro Valley, California
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AQI 33
Good
6.44μg/m³
PM2.5
32.97μg/m³
PM10
35.19ppb
O3
0.71ppb
SO2
4.62ppb
NO2
0.35ppm
CO
AQI 33
Good
6.44μg/m³
PM2.5
32.97μg/m³
PM10
35.19ppb
O3
0.71ppb
SO2
4.62ppb
NO2
0.35ppm
CO
AQI 33
Good
6.47μg/m³
PM2.5
32.48μg/m³
PM10
34.78ppb
O3
0.70ppb
SO2
4.66ppb
NO2
0.36ppm
CO
AQI 38
Good
6.57μg/m³
PM2.5
30.34μg/m³
PM10
31.58ppb
O3
0.59ppb
SO2
4.83ppb
NO2
0.40ppm
CO
AQI 38
Good
6.51μg/m³
PM2.5
30.50μg/m³
PM10
32.12ppb
O3
0.59ppb
SO2
4.74ppb
NO2
0.40ppm
CO
AQI 38
Good
6.86μg/m³
PM2.5
30.55μg/m³
PM10
30.25ppb
O3
0.59ppb
SO2
5.17ppb
NO2
0.41ppm
CO
Air quality and pollutant data for California, 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 Castro Valley, California is updated every hour for accuracy.
In the past 24 hours, the air quality in Castro Valley, California was at its worst at 11:00:00 on 2026-06-12.
In the last 24 hours, the best air quality in Castro Valley, California was observed at 04:00:00 on 2026-06-13.
As of now, the AQI in Castro Valley, California is 33, indicating Good conditions.
Castro Valley, California air has the highest levels of PM2.5.
Poor air quality in Castro Valley, California means it's advisable to stay indoors and wear a mask for your protection.
PM2.5 levels in Castro Valley, California are currently 6.446 μg/m3.
The PM10 concentration in Castro Valley, California is 32.076 μg/m3 at the moment.
The current carbon monoxide (CO) concentration in Castro Valley, California is 0.362 ppm.
Currently, Castro Valley, California has a sulfur dioxide (SO2) concentration of 0.71 ppb.
The current ozone (O3) level in Castro Valley, California at the moment is 34.659 ppm.
Nitrogen dioxide (NO2) level in Castro Valley, California at the moment is 4.69 ppb.
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