Median AQI
53
Moderate
Ohio · County air quality · 2025
Cuyahoga County, Ohio
Median AQI 53 (Moderate). 43.6% of monitored days rated Good, direct from EPA Air Quality System stations.
- 53
- Median AQI
- 43.6%
- Good-air days
- 0
- Unhealthy days
- 4%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Cuyahoga County's air is moderate on balance, among the most polluted counties nationally, a median AQI of 53 with 43.6% of 305 monitored days in the Good band, driven mainly by PM2.5.
- 53
- median AQI · Moderate
- 43.6%
- days rated Good
- PM2.5
- main pollutant
- 4%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 150.
Data updated July 2026
- Good · 133 d · 43.6%
- Moderate · 168 d · 55.1%
- USG · 4 d · 1.3%
How did Cuyahoga County's air break down in 2025?
Across 305 monitored days, 133 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 150 (USG).
EPA AQS →Air quality data from EPA Air Quality System (2025). 305 days monitored. Median AQI: 53 (Moderate).
Insights: Cuyahoga County, Ohio. EPA monitors recorded a median Air Quality Index of 53 across 305 measured days in 2025, earning a Moderate classification and a Poor health grade. Of those days, 133 (44%) fell in the Good band (AQI 0–50), 168 (55%) registered Moderate readings, and 4 (1%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 80, while the worst single-day peak hit 150 (USG). Residents averaged about 13.1 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as PM2.5 (173 days), Ozone (113 days), PM10 (15 days), CO (4 days). Across the 2020–2025 trend window, good days shifted by -15 and the median AQI moved -1 points, placing the multi-year trajectory at improving. The worst single reading over the 2020–2025 window was AQI 150, usg but never Unhealthy. Nearby counties show comparable readings: Allen (65.9% good, AQI 43); Ashtabula (81.2% good, AQI 43); Athens (80.3% good, AQI 33); Belmont (63.0% good, AQI 42); Butler (33.3% good, AQI 55); Clark (59.4% good, AQI 46).
Air Quality Summary
Good Days
43.6%
133 of 305 monitored days
-31.4pp vs 75% target
Max AQI Recorded
150
USG
Health Grade
Poor
90th-pct AQI 80
Cuyahoga County, Good days share 43.6%
National avg
Share of monitored days at AQI 0-50 (Good band).
Cuyahoga County, Unhealthy-or-worse share 0.0%
National avg
Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).
AQI Day Breakdown (2025)
Distribution of 305 monitored days across EPA AQI categories.
Good
133
44%
Moderate
168
55%
USG
4
1%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Cuyahoga County.
- PM2.5 · 173 days · 56.7%
- Ozone · 113 days · 37.0%
- PM10 · 15 days · 4.9%
- CO · 4 days · 1.3%
Health Impact Assessment
Poor
Cuyahoga County's air quality is rated Poor based on 43.6% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 43.6% of monitored days in 2025, with a median AQI of 53. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is PM2.5, driving AQI on 173 of 305 monitored days.
5-Year Air Quality Trend
Air quality is improving in Cuyahoga County. Best year: 2020 (148 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 148 | 208 | 9 | 1 | 54 | 152 |
| 2021 | 100 | 261 | 4 | 0 | 57 | 115 |
| 2022 | 137 | 220 | 6 | 2 | 54 | 158 |
| 2023 | 117 | 235 | 9 | 3 | 57 | 234 |
| 2024 | 136 | 224 | 6 | 0 | 54 | 122 |
| 2025 | 133 | 168 | 4 | 0 | 53 | 150 |
How does Cuyahoga County compare?
How Cuyahoga County compares
Good-day share worse than US avg
Cuyahoga County 43.6%
Allen County, Ohio 65.9%
US average 76.5%
Median AQI worse than US avg
Cuyahoga County 53
Allen County, Ohio 43
US average 38
Unhealthy days / yr about average
Cuyahoga County 0
Allen County, Ohio 0
US average 0
Other Counties in Ohio
Air quality comparison for nearby counties in Ohio.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Cuyahoga County.
Bexar County, Texas
AQI 53 · 39.8% good
Cook County, Illinois
AQI 53 · 40.5% good
Dallas County, Texas
AQI 53 · 41.0% good
Jefferson County, Alabama
AQI 53 · 36.8% good
Kings County, California
AQI 53 · 39.8% good
Lake County, Indiana
AQI 53 · 38.8% good
What Cuyahoga County's air means for you
The air here stays in the breathable range year-round, with PM2.5 the main thing to watch.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-PM2.5 days, the guide explains what a median of 53 means for exposure. Health guidance
- See how Cuyahoga County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Cuyahoga County with its Ohio neighbours before drawing a conclusion about the region. All of Ohio
Based on 305 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.
More Air Quality Data
Air Quality Guides
Frequently Asked Questions
What is the air quality in Cuyahoga County, Ohio? ▼
Cuyahoga County has a median Air Quality Index (AQI) of 53, rated "Moderate." 43.6% of monitored days (133 out of 305) had good air quality in 2025.
What is the main pollutant in Cuyahoga County? ▼
The primary pollutant in Cuyahoga County is Fine Particles (PM2.5), which was the main AQI driver on 173 days (57% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Cuyahoga County have? ▼
In 2025, Cuyahoga County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 150.
Is the air quality in Cuyahoga County getting better or worse? ▼
Air quality in Cuyahoga County is improving based on 5-year trends (2020-2025). Best year: 2020 with 148 good days. Worst year: 2021 with 100 good days.
What does AQI 53 mean for health? ▼
Cuyahoga County's median AQI of 53 falls in the "Moderate" category. See the <a href="/guides/understanding-aqi" class="underline">AQI category guide</a> for what each range means for health.
How does Cuyahoga County compare to other counties in Ohio? ▼
Cuyahoga County has 43.6% good air days. Nearby counties in Ohio: Allen (65.9% good), Ashtabula (81.2% good), Athens (80.3% good), Belmont (63.0% good), Butler (33.3% good), Clark (59.4% good).
What is the 90th percentile AQI in Cuyahoga County? ▼
The 90th percentile AQI for Cuyahoga County is 80, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 150 (USG).
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.
Informational only, not professional advice. Data from EPA AQS. See our disclaimer.
Every figure on PlainAir is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.