Stay updated with real-time air quality in Portland, Maine 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)
24
Good
Portland, Maine
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
3.48 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
10.02 μg/m³
0
55
155
255
425
605+
25.86 ppb
0
55
71
86
201
201+
0.21 ppb
0
36
76
186
605
1005+
1.89 ppb
0
54
101
361
1250
2050+
0.16 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
Low
Portland, Maine
Portland, Maine
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AQI 24
Good
3.10μg/m³
PM2.5
8.88μg/m³
PM10
25.80ppb
O3
0.21ppb
SO2
1.50ppb
NO2
0.15ppm
CO
AQI 23
Good
3.59μg/m³
PM2.5
14.81μg/m³
PM10
25.09ppb
O3
0.37ppb
SO2
1.62ppb
NO2
0.15ppm
CO
AQI 24
Good
3.44μg/m³
PM2.5
10.20μg/m³
PM10
25.71ppb
O3
0.22ppb
SO2
1.51ppb
NO2
0.16ppm
CO
AQI 23
Good
3.43μg/m³
PM2.5
11.55μg/m³
PM10
24.63ppb
O3
0.28ppb
SO2
1.55ppb
NO2
0.15ppm
CO
AQI 23
Good
3.60μg/m³
PM2.5
14.09μg/m³
PM10
25.19ppb
O3
0.46ppb
SO2
1.69ppb
NO2
0.15ppm
CO
AQI 24
Good
3.30μg/m³
PM2.5
13.86μg/m³
PM10
25.75ppb
O3
0.41ppb
SO2
1.67ppb
NO2
0.16ppm
CO
Air quality and pollutant data for Maine, 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 Portland, Maine is updated every hour for accuracy.
In the past 24 hours, the air quality in Portland, Maine was at its worst at 08:00:00 on 2026-08-13.
In the last 24 hours, the best air quality in Portland, Maine was observed at 02:00:00 on 2026-08-14.
As of now, the AQI in Portland, Maine is 24, indicating Good conditions.
Portland, Maine air has the highest levels of O3.
Poor air quality in Portland, Maine means it's advisable to stay indoors and wear a mask for your protection.
PM2.5 levels in Portland, Maine are currently 3.48 μg/m3.
The PM10 concentration in Portland, Maine is 10.015 μg/m3 at the moment.
The current carbon monoxide (CO) concentration in Portland, Maine is 0.161 ppm.
Currently, Portland, Maine has a sulfur dioxide (SO2) concentration of 0.213 ppb.
The current ozone (O3) level in Portland, Maine at the moment is 25.864 ppm.
Nitrogen dioxide (NO2) level in Portland, Maine at the moment is 1.892 ppb.
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