Median AQI
39
Good
New Jersey · County air quality · 2025
Ocean County, New Jersey
Median AQI 39 (Good). 78.8% of monitored days rated Good, direct from EPA Air Quality System stations.
- 39
- Median AQI
- 78.8%
- Good-air days
- 1
- Unhealthy days
- 53%
- Cleaner than US counties
Ocean County's 2025 annual median AQI is 39 (Good), with 78.8% Good days
According to the U.S. EPA Air Quality System, Ocean County, New Jersey posted a 2025 median AQI of 39 (Good) across 363 monitored days, with 78.8% rated Good and 1 unhealthy or worse. This is an annual comparison, not today's advisory.
Data source EPA Air Quality System (AQS)
- Cleaner than US
- Ocean County's 78.8% Good-day share places it cleaner than 53% of US counties in 2025.
- Closest median-AQI peer
- Aiken County (90.6% Good, median AQI 39) is the closest nationwide median-AQI peer to Ocean County.
- 2020–2025 trend
- Ocean County's floor-qualifying Good-day share is stable from 2020 to 2025 (81.5% → 78.8%).
- Median AQI
- Median AQI: 39
The verdict
According to EPA Air Quality System monitoring data, Ocean County's air is good on balance, cleaner than the median US county, a median AQI of 39 with 78.8% of 363 monitored days in the Good band, driven mainly by Ozone.
- 39
- median AQI · Good
- 78.8%
- days rated Good
- Ozone
- main pollutant
- 53%
- cleaner than US counties
1 day reached Unhealthy or worse; the worst single reading hit AQI 154.
Annual release change
What changed in the 2025 EPA annual release
- Ocean County's Good-day share rose from 76.5% to 78.8% between the 2024 and 2025 EPA annual releases, a change of +2.3 percentage points.
- Ocean County's peak single-day AQI rose from 140 to 154 between the 2024 and 2025 EPA annual releases, a change of +14 points.
- Ocean County's Unhealthy-category days rose from 0 to 1 between the 2024 and 2025 EPA annual releases, a change of +1 days.
Data updated August 2026
- Good · 286 d · 78.8%
- Moderate · 76 d · 20.9%
- Unhealthy · 1 d · 0.3%
How did Ocean County's air break down in 2025?
Across 363 monitored days, 286 fell in the Good band (AQI 0–50) and 1 reached Unhealthy or worse. The worst single day peaked at AQI 154 (Unhealthy).
EPA AQS →Air quality data from EPA Air Quality System (2025). 363 days monitored. Median AQI: 39 (Good).
Insights: Ocean County, New Jersey. EPA monitors recorded a median Air Quality Index of 39 across 363 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 286 (79%) fell in the Good band (AQI 0–50), 76 (21%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 58, while the worst single-day peak hit 154 (Unhealthy). Residents averaged about 23.6 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (193 days), PM2.5 (170 days). Across the 2020–2025 trend window, the share of monitored days rated Good shifted by -2.7 points and the median AQI moved +1 points, placing the multi-year trajectory at stable. The annual record contains 1 day at Unhealthy or worse. On that day, the EPA recommends that sensitive groups limit prolonged outdoor exertion. Nearby counties show comparable readings: Atlantic (82.2% good, AQI 36); Bergen (71.1% good, AQI 40); Camden (65.6% good, AQI 44); Cumberland (76.2% good, AQI 40); Gloucester (78.7% good, AQI 39); Hudson (71.5% good, AQI 41).
Air Quality Summary
Good Days
78.8%
286 of 363 monitored days
3.8pp vs 75% target
Max AQI Recorded
154
Unhealthy
Health Grade
Good
90th-pct AQI 58
Ocean County, Good days share 78.8%
National avg
Share of monitored days at AQI 0-50 (Good band).
Ocean County, Unhealthy-or-worse share 2.8%
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 363 monitored days across EPA AQI categories.
Good
286
79%
Moderate
76
21%
USG
0
0%
Unhealthy
1
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Ocean County.
- Ozone · 193 days · 53.2%
- PM2.5 · 170 days · 46.8%
Health Impact Assessment
Good
Ocean County's air quality is rated Good based on 78.8% good air days. There were 1 unhealthy days in 2025 when outdoor activity should be limited.
Air quality is acceptable most days, but 0 days reached "Unhealthy for Sensitive Groups" (AQI 101-150) and peak AQI reached 154. Sensitive groups should monitor real-time conditions at AirNow.gov.
The dominant pollutant is Ozone, driving AQI on 193 of 363 monitored days.
5-Year Air Quality Trend
Air quality is stable in Ocean County. Highest Good-day share: 2020 (81.5%, 290 of 356 monitored days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 290 | 66 | 0 | 0 | 38 | 84 |
| 2021 | 253 | 100 | 4 | 0 | 42 | 126 |
| 2022 | 287 | 68 | 3 | 0 | 40 | 105 |
| 2023 | 261 | 95 | 7 | 1 | 42 | 248 |
| 2024 | 280 | 82 | 4 | 0 | 41 | 140 |
| 2025 | 286 | 76 | 0 | 1 | 39 | 154 |
How does Ocean County compare?
How Ocean County compares
Good-day share better than US avg
Ocean County 78.8%
Aiken County, South Carolina 90.6%
US average 76.0%
Median AQI about average
Ocean County 39
Aiken County, South Carolina 39
US average 39
Unhealthy days / yr about average
Ocean County 1
Aiken County, South Carolina 0
US average 1
Counties with a similar median AQI
Nationwide peers within about the same annual median AQI as Ocean County (39), not geographic neighbors.
Aiken County, South Carolina
Median AQI 39 · 90.6% Good-day share
Albany County, New York
Median AQI 39 · 68.5% Good-day share
Anderson County, Tennessee
Median AQI 39 · 94.3% Good-day share
Bay County, Michigan
Median AQI 39 · 70.4% Good-day share
Berkeley County, West Virginia
Median AQI 39 · 83.6% Good-day share
Boyd County, Kentucky
Median AQI 39 · 80.0% Good-day share
Same primary pollutant: Ozone
Ozone led the AQI on the most monitored days here. These peers share that driver and the closest Good-day share (a second relationship type beyond median-AQI neighbors).
Gloucester County, New Jersey
78.7% Good-day share · median AQI 39
Sheboygan County, Wisconsin
78.9% Good-day share · median AQI 41
Bossier County, Louisiana
78.9% Good-day share · median AQI 42
Cheshire County, New Hampshire
78.9% Good-day share · median AQI 37
Fayette County, Pennsylvania
78.9% Good-day share · median AQI 40
Warren County, Pennsylvania
78.7% Good-day share · median AQI 35
New Jersey counties on the map
Geographic containment only, other monitored counties in New Jersey, independent of AQI or pollutant match.
What Ocean County's air means for you
On most days the air here is fine, but Ozone drives 1 unhealthy-or-worse day a year that sensitive groups should plan around.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-Ozone days, the guide explains what a median of 39 means for exposure. Health guidance
- See how Ocean County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Ocean County with its New Jersey neighbours before drawing a conclusion about the region. All of New Jersey
Based on 363 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.
Keep exploring the annual AQI record
Air-quality reading list
Frequently Asked Questions
What is the air quality in Ocean County, New Jersey? ▼
Ocean County has a median Air Quality Index (AQI) of 39, rated "Good." 78.8% of monitored days (286 out of 363) had good air quality in 2025.
What is the main pollutant in Ocean County? ▼
The primary pollutant in Ocean County is Ozone (O3), which was the main AQI driver on 193 days (53% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Ocean County have? ▼
In 2025, Ocean County recorded 1 unhealthy air days (1 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 154.
Is the air quality in Ocean County getting better or worse? ▼
Air quality in Ocean County is stable across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2020 at 81.5% (290 of 356 days). Lowest qualifying Good-day share: 2021 at 70.9% (253 of 357 days).
What does AQI 39 mean for health? ▼
Ocean County's median AQI of 39 falls in the "Good" category. See the AQI category guide for what each range means for health.
How does Ocean County compare to other counties in New Jersey? ▼
Ocean County has 78.8% good air days. Nearby counties in New Jersey: Atlantic (82.2% good), Bergen (71.1% good), Camden (65.6% good), Cumberland (76.2% good), Gloucester (78.7% good), Hudson (71.5% good).
What is the 90th percentile AQI in Ocean County? ▼
The 90th percentile AQI for Ocean County is 58, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 154 (Unhealthy).
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. Spotted a figure that looks wrong? Report a correction.
Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files for Ocean County, New Jersey · 2020–2025
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Every figure on PlainAirData 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.