Air quality · Ohio
Air quality in Ohio
Across the 7 Ohio ZIPs with EPA county air-quality data, the median day is Moderate in all 7 (median AQI 53–54). 4 days across those counties reached Unhealthy or worse in 2025. This is a 2025 county annual summary, not a live reading.
Last verified 2026-09-24 · methodology
Air quality by ZIP code in Ohio
EPA's 2025 annual summary for each ZIP's county. Median AQI is the typical day; lower is cleaner.
| ZIP | Median AQI | Good days | Unhealthy or worse |
|---|---|---|---|
| 44113ClevelandCuyahoga County | 53 Moderate | 158 of 365 | 0 |
| 43215ColumbusFranklin County | 53 Moderate | 147 of 365 | 1 |
| 45202CincinnatiHamilton County | 54 Moderate | 125 of 365 | 1 |
| 44115Cleveland (Downtown)Cuyahoga County | 53 Moderate | 158 of 365 | 0 |
| 44114Cleveland (Downtown East)Cuyahoga County | 53 Moderate | 158 of 365 | 0 |
| 45220Cincinnati (Clifton)Hamilton County | 54 Moderate | 125 of 365 | 1 |
| 43017Dublin (OH)Franklin County | 53 Moderate | 147 of 365 | 1 |
County-level figures from EPA Air Quality System (AQS), annual county summary, joined to each ZIP by county. None of them is a measurement at a specific address.
What lands here
Pages show the 2025 median AQI category (Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, Hazardous) for the ZIP's county, plus the year's max/90th-percentile AQI and day-count breakdown by category.
Source & refresh
EPA Air Quality System (AQS), annual county summary. Refreshed annual (epa aqs publication). Primary source →
Ohio top concern
Lead service lines, Great Lakes erosion
Ohio has heavy LCRR obligations in Cleveland, Cincinnati, Columbus, Toledo. Lake Erie shoreline erosion expands FEMA AE zones in some lakefront counties. Tornado exposure on the Indiana/Ohio border.
See Ohio state page for the full state-level rollup across all 12 dimensions.
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