Stay updated with real-time air quality in Portsmouth, New Hampshire 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)
34
Good
Portsmouth, New Hampshire
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
6.00 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
36.95 μg/m³
0
55
155
255
425
605+
33.02 ppb
0
55
71
86
201
201+
0.60 ppb
0
36
76
186
605
1005+
9.81 ppb
0
54
101
361
1250
2050+
0.28 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
Low
Portsmouth, New Hampshire
Portsmouth, New Hampshire
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AQI 34
Good
6.00μg/m³
PM2.5
36.93μg/m³
PM10
33.02ppb
O3
0.60ppb
SO2
9.81ppb
NO2
0.28ppm
CO
AQI 36
Good
6.29μg/m³
PM2.5
39.32μg/m³
PM10
33.75ppb
O3
0.61ppb
SO2
9.74ppb
NO2
0.27ppm
CO
AQI 34
Good
5.83μg/m³
PM2.5
35.83μg/m³
PM10
37.05ppb
O3
0.65ppb
SO2
9.87ppb
NO2
0.27ppm
CO
AQI 31
Good
5.46μg/m³
PM2.5
13.78μg/m³
PM10
34.39ppb
O3
0.62ppb
SO2
8.51ppb
NO2
0.31ppm
CO
AQI 35
Good
5.82μg/m³
PM2.5
27.95μg/m³
PM10
38.23ppb
O3
0.66ppb
SO2
9.94ppb
NO2
0.26ppm
CO
AQI 32
Good
5.22μg/m³
PM2.5
14.05μg/m³
PM10
35.13ppb
O3
0.62ppb
SO2
8.04ppb
NO2
0.30ppm
CO
Air quality and pollutant data for New Hampshire, 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 Portsmouth, New Hampshire is updated every hour for accuracy.
In the past 24 hours, the air quality in Portsmouth, New Hampshire was at its worst at 02:00:00 on 2025-12-28.
In the last 24 hours, the best air quality in Portsmouth, New Hampshire was observed at 10:00:00 on 2025-12-27.
As of now, the AQI in Portsmouth, New Hampshire is 34, indicating Good conditions.
Portsmouth, New Hampshire air has the highest levels of PM10.
Poor air quality in Portsmouth, New Hampshire means it's advisable to stay indoors and wear a mask for your protection.
PM2.5 levels in Portsmouth, New Hampshire are currently 5.997 μg/m3.
The PM10 concentration in Portsmouth, New Hampshire is 36.948 μg/m3 at the moment.
The current carbon monoxide (CO) concentration in Portsmouth, New Hampshire is 0.277 ppm.
Currently, Portsmouth, New Hampshire has a sulfur dioxide (SO2) concentration of 0.6 ppb.
The current ozone (O3) level in Portsmouth, New Hampshire at the moment is 33.015 ppm.
Nitrogen dioxide (NO2) level in Portsmouth, New Hampshire at the moment is 9.815 ppb.
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