Air quality in Brno, Southeast, Czechia today

Mr. Duck’s Air Quality Score

Unhealthy for sensitive groups for Brno, Southeast, Czechia

⚠️ 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 overall air quality today is classified as USG. The main pollutant is PM2.5 (fine particles). The data pertain to Brno, located in the Southeast region of Czechia, and are shown via OpenAQ. The assessment is based on 22 valid measurements, which together determine the USG rating.

The reported PM2.5 concentration is 46.1 µg/m³ and the PM10 concentration is 57.8 µg/m³, representing the latest values from the measurement set. These figures come from the 22 valid observations used in the analysis. All values are expressed in micrograms per cubic meter. The PM2.5 and PM10 figures serve as the reference concentrations for the USG classification. 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 Brno air‑quality feed contains 40 recorded rows from nine monitoring stations and reports on eleven pollutants that are part of the OpenAQ network: carbon monoxide (CO), nitrogen monoxide (NO), nitrogen dioxide (NO2), ozone (O3), particulate matter PM1, PM10 and PM2.5, relative humidity, sulfur dioxide (SO2), temperature and the particle counter UM003. For the current snapshot, recent measurements are available for PM2.5, PM10, PM1, relative humidity, temperature, UM003, NO and NO2. The newest timestamps are all from 2026‑02‑10 18:00 UTC for the particulate and meteorological variables, while the latest NO value dates back to 2024‑03‑11 10:00 UTC. No recent rows are present for CO, O3 or SO2, so those compounds are listed as measured but lack current data.

Across the available pollutants the data show a broad spread. PM2.5 values range from 1.33 µg/m³ up to 63.65 µg/m³ with a median of 19.9 µg/m³; PM10 spans 5.08 µg/m³ to 57.8 µg/m³ (median 17.8 µg/m³); PM1 varies between 0.61 µg/m³ and 38.91 µg/m³ (median 13.39 µg/m³). Relative humidity is recorded between 49.9 % and 63.4 % (median 55.7 %); temperature covers 6.81 °C to 24.79 °C (median 16.80 °C); and UM003 particle counts range from 315.85 to 3211.70 particles/cm³ (median 1370.05). The number of rows per pollutant differs markedly: eight rows for PM2.5, five for PM10, four each for PM1, humidity, temperature and UM003, and only three rows each for NO and NO2. Overall freshness shows that 23 rows are within the last 30 days, 12 are older, and five have unknown timestamps, indicating that while many recent observations exist, a notable share of the dataset is dated. Consequently, the reported conditions can vary considerably across locations and times within Brno, and the picture is incomplete for some gases such as CO, O3 and SO2.

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 dataset for Brno includes 22 valid measurements and is updated within 30 days, with the latest update recorded on 2026-02-10T18:00:00+00:00. These values reflect the monitoring period covered by the sensors and are intended to give a general view of current conditions. Please note that air quality can vary by location and time within the city, so individual experiences may differ.

OpenAQ station rows