Cincinnati, Ohio Air Quality

Cincinnati air quality today — the AQI, the main pollutant, and whether it’s safe to exercise outside right now

Cincinnati, OH · Air quality right now

The air quality index in Cincinnati, OH is 50 (Good) right now — safe for outdoor activity.

Is it safe to be outside in Cincinnati today?

AQI 50 Yes — air quality is Good

Air is clean — great for outdoor activity.Main pollutant: PM2.5Observed 1:00 AM EDT

Pollutants right now

ExerciseOK to run — no air-quality limits on outdoor exercise.

How to read Cincinnati’s air quality

Guides: The AQI Scale, Explained · Air Quality Alerts, Decoded · How to Read a Wildfire Smoke Map · Why Wildfire Smoke Travels 1,000 Miles.

Air quality over time in Cincinnati

Across the EPA’s county records from 2020 to 2025, Cincinnati’s cleanest year was 2024 (median AQI 52) and its most polluted was 2021 (median AQI 56); the typical (median) day has held roughly steady since 2020.

Cincinnati’s county air-quality record by year — the median and days in each AQI category, from the EPA’s Annual AQI by County summaries.
YearMedian AQIUnhealthy+Main pollutantUSGModerateGood
2020550PM2.57254105
2021560PM2.55251109
2022541PM2.53236125
2023542PM2.517217129
2024520PM2.511191164
2025541PM2.512227125

“USG” is Unhealthy for Sensitive Groups (AQI 101–150); “Unhealthy+” combines the Unhealthy, Very Unhealthy, and Hazardous days. In 2024 the EPA tightened the annual fine-particle (PM2.5) standard to 9 µg/m³ from the previous 12 µg/m³, so counties near the old limit read worse against the new one. Source: EPA AQS annual summaries, 20202025.

Frequently asked

What was the worst year for air quality in Cincinnati?
In the EPA's 2020–2025 county records, 2023 had the most days above AQI 100: 19 days (17 Unhealthy for Sensitive Groups, 2 Unhealthy or worse). The highest median AQI came in 2021 (56; 2023's was 54).
How many unhealthy air days does Cincinnati have?
Across 2020–2025, 3% of the days reported for Cincinnati's county had an AQI above 100 (59 of 2192), about 10 days a year. 2025 had 13 days.
What's the main air pollutant in Cincinnati?
PM2.5: it drove Cincinnati's county AQI on the most days in every year of the EPA's 2020–2025 records.