Air quality in Baltimore, Maryland, United States of America today

Mr. Duck’s Air Quality Score

Moderate air today for Baltimore, Maryland, United States of America

⚠️ This website is currently under active development. Some data may be incomplete or temporarily inaccurate. For health-critical decisions, please verify information through official government or environmental sources.

Categories follow US EPA AQI breakpoints for PM (estimate from latest valid measurements; this project does not compute EPA NowCast/24-hour AQI yet).

This friendly indicator summarizes the latest city readings. For health guidance, please see: EPA AirNow or WHO.

Air quality today

The air quality in Baltimore, Maryland is currently classified as Moderate. The primary pollutant identified is PM2.5 (fine particles). Measurements show a PM2.5 concentration of 32.42 µg/m³ based on seven valid observations reported through OpenAQ.

These data reflect the present conditions without implying any trend or forecast. This page is informational; for health guidance, use official sources such as EPA AirNow or WHO.

Latest sensor values

PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).

What the data includes

The Baltimore air‑quality dataset contains eight measured variables – nitrogen monoxide (NO), nitrogen dioxide (NO2), total nitrogen oxides (NOX), ozone (O3), particulate matter of 1 µm (PM1), 2.5 µm (PM2.5) and 10 µm (PM10) size fractions, relative humidity and temperature – drawn from a total of three monitoring stations. Across the whole set only two rows are recent, with the latest updates recorded on 2026‑02‑11 for PM2.5, NO2, PM1, relative humidity and temperature; the other pollutants have their most recent values from mid‑2023 (NO, NOX) or late‑2025 (O3, PM10). This means that while some metrics are refreshed within the last week, several key gases are based on data older than a year.

For the freshest variables the median and minimum values coincide, indicating very little variation in the limited recent sample. PM2.5 shows a narrow range from 18 µg/m³ (minimum) to about 32.4 µg/m³ (maximum), with the 10th percentile also at 18 µg/m³ and the 90th percentile near 29.5 µg/m³, suggesting most recent readings cluster around the median of 18 µg/m³. NO2 values are similarly tight, spanning from 0.008 ppm to 0.0283 ppm, with a median of 0.01815 ppm and the 90th percentile at 0.02627 ppm. In contrast, older measurements such as NO (0.0004 ppm) and NOX (0.0034 ppm) each have only a single recorded value, so no spread can be assessed.

Overall the dataset provides coverage for all listed pollutants but is uneven in timeliness: half of the variables are updated within the past week, while the remaining half rely on data that is several months to over two years old. Consequently, city‑wide conditions may differ across locations and times, and users should keep in mind that the snapshot reflects a mix of very recent and dated observations.

Learn more about sources and filtering: About the data.

Trusted references: WHO (Air pollution) · US EPA AirNow · European Environment Agency (Air)

Latest sensor values (bars)

PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).

Data notes

The data shown reflects seven valid measurements and was updated today (2026‑02‑11T00:00:00+00:00). These readings provide a snapshot of current conditions, but air quality can vary across different neighborhoods and at different times of day within Baltimore. Consequently, the values represent an approximate overview rather than precise, location‑specific information for every part of the city.

OpenAQ station rows