Stay updated with real-time air quality in Hillsborough, 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)
54
Moderate
Hillsborough, California
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
11.26 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
41.07 μg/m³
0
55
155
255
425
605+
5.12 ppb
0
55
71
86
201
201+
0.56 ppb
0
36
76
186
605
1005+
11.23 ppb
0
54
101
361
1250
2050+
0.53 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
Low
Hillsborough, California
Hillsborough, California
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AQI 56
Moderate
11.81μg/m³
PM2.5
31.36μg/m³
PM10
3.88ppb
O3
0.55ppb
SO2
13.33ppb
NO2
0.60ppm
CO
AQI 56
Moderate
11.81μg/m³
PM2.5
31.36μg/m³
PM10
3.88ppb
O3
0.55ppb
SO2
13.33ppb
NO2
0.60ppm
CO
AQI 56
Moderate
12.16μg/m³
PM2.5
39.45μg/m³
PM10
7.97ppb
O3
0.55ppb
SO2
13.47ppb
NO2
0.56ppm
CO
AQI 58
Moderate
13.41μg/m³
PM2.5
46.18μg/m³
PM10
6.42ppb
O3
0.55ppb
SO2
12.77ppb
NO2
0.68ppm
CO
AQI 58
Moderate
13.41μg/m³
PM2.5
46.18μg/m³
PM10
6.42ppb
O3
0.55ppb
SO2
12.77ppb
NO2
0.68ppm
CO
AQI 56
Moderate
12.34μg/m³
PM2.5
44.40μg/m³
PM10
3.66ppb
O3
0.54ppb
SO2
13.23ppb
NO2
0.35ppm
CO
The air quality data for California, USA is gathered from reliable sources such as satellites and monitoring stations, adhering to US EPA guidelines. With the help of advanced algorithms and machine learning, factors like traffic and population density are analyzed to deliver accurate and dependable results.
Source: Ambee Data Sources
Air quality updates for Hillsborough, California are available every hour.
Hillsborough, California experienced its worst air quality at 12:00:00, 2025-12-09.
The best air quality in Hillsborough, California was observed at 12:00:00 on 2025-12-09.
The air quality in Hillsborough, California right now is Moderate, with an AQI of 54.
In Hillsborough, California, PM2.5 is the most frequently found pollutant.
When air quality in Hillsborough, California is compromised, staying indoors and wearing a mask can reduce health risks.
Hillsborough, California currently has a PM2.5 concentration of 11.255 μg/m3.
Hillsborough, California currently has a PM10 concentration of 41.069 μg/m3.
The current carbon monoxide (CO) level in Hillsborough, California is 0.525 ppm.
The current sulfur dioxide (SO2) concentration in Hillsborough, California is 0.56 ppb.
Hillsborough, California currently has an ozone (O3) concentration of 5.119 ppm.
The current level of nitrogen dioxide (NO2) in Hillsborough, California is 11.234 ppb.
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