Median AQI
37
Good
Florida · County air quality · 2025
Alachua County, Florida
Median AQI 37 (Good). 90.1% of monitored days rated Good, direct from EPA Air Quality System stations.
- 37
- Median AQI
- 90.1%
- Good-air days
- 0
- Unhealthy days
- 76%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Alachua County's air is good on balance, cleaner than most US counties, a median AQI of 37 with 90.1% of 272 monitored days in the Good band, driven mainly by PM2.5.
- 37
- median AQI · Good
- 90.1%
- days rated Good
- PM2.5
- main pollutant
- 76%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 69.
Data updated July 2026
- Good · 245 d · 90.1%
- Moderate · 27 d · 9.9%
How did Alachua County's air break down in 2025?
Across 272 monitored days, 245 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 69 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 272 days monitored. Median AQI: 37 (Good).
Insights: Alachua County, Florida. EPA monitors recorded a median Air Quality Index of 37 across 272 measured days in 2025, earning a Good classification and a Excellent health grade. Of those days, 245 (90%) fell in the Good band (AQI 0–50), 27 (10%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 50, while the worst single-day peak hit 69 (Moderate). Residents averaged about 27.0 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as PM2.5 (145 days), Ozone (127 days). Across the 2020–2025 trend window, good days shifted by -29 and the median AQI moved -5 points, placing the multi-year trajectory at improving. The worst single reading over the 2020–2025 window was AQI 69, moderate but never Unhealthy. Nearby counties show comparable readings: Baker (69.1% good, AQI 45); Bay (60.6% good, AQI 46); Brevard (89.7% good, AQI 37); Broward (72.4% good, AQI 43); Citrus (67.8% good, AQI 44); Collier (67.4% good, AQI 43).
Air Quality Summary
Good Days
90.1%
245 of 272 monitored days
15.1pp vs 75% target
Max AQI Recorded
69
Moderate
Health Grade
Excellent
90th-pct AQI 50
Alachua County, Good days share 90.1%
National avg
Share of monitored days at AQI 0-50 (Good band).
Alachua 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 272 monitored days across EPA AQI categories.
Good
245
90%
Moderate
27
10%
USG
0
0%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Alachua County.
- PM2.5 · 145 days · 53.3%
- Ozone · 127 days · 46.7%
Health Impact Assessment
Excellent
Alachua County's air quality is rated Excellent based on 90.1% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 90.1% of monitored days in 2025, with a median AQI of 37. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is PM2.5, driving AQI on 145 of 272 monitored days.
5-Year Air Quality Trend
Air quality is improving in Alachua County. Best year: 2021 (308 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 274 | 91 | 1 | 0 | 42 | 105 |
| 2021 | 308 | 56 | 0 | 0 | 39 | 84 |
| 2022 | 292 | 70 | 0 | 0 | 41 | 84 |
| 2023 | 270 | 94 | 1 | 0 | 40 | 104 |
| 2024 | 300 | 49 | 0 | 0 | 38 | 94 |
| 2025 | 245 | 27 | 0 | 0 | 37 | 69 |
How does Alachua County compare?
How Alachua County compares
Good-day share better than US avg
Alachua County 90.1%
Baker County, Florida 69.1%
US average 76.5%
Median AQI better than US avg
Alachua County 37
Baker County, Florida 45
US average 38
Unhealthy days / yr about average
Alachua County 0
Baker County, Florida 0
US average 0
Other Counties in Florida
Air quality comparison for nearby counties in Florida.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Alachua County.
Beltrami County, Minnesota
AQI 37 · 88.8% good
Benewah County, Idaho
AQI 37 · 74.6% good
Brevard County, Florida
AQI 37 · 89.7% good
Brown County, Indiana
AQI 37 · 94.5% good
Brown County, Wisconsin
AQI 37 · 79.0% good
Caldwell County, North Carolina
AQI 37 · 96.2% good
What Alachua 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 37 means for exposure. Health guidance
- See how Alachua County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Alachua County with its Florida neighbours before drawing a conclusion about the region. All of Florida
Based on 272 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 Alachua County, Florida? ▼
Alachua County has a median Air Quality Index (AQI) of 37, rated "Good." 90.1% of monitored days (245 out of 272) had good air quality in 2025.
What is the main pollutant in Alachua County? ▼
The primary pollutant in Alachua County is Fine Particles (PM2.5), which was the main AQI driver on 145 days (53% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Alachua County have? ▼
In 2025, Alachua County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 69.
Is the air quality in Alachua County getting better or worse? ▼
Air quality in Alachua County is improving based on 5-year trends (2020-2025). Best year: 2021 with 308 good days. Worst year: 2025 with 245 good days.
What does AQI 37 mean for health? ▼
Alachua County's median AQI of 37 falls in the "Good" category. See the <a href="/guides/understanding-aqi" class="underline">AQI category guide</a> for what each range means for health.
How does Alachua County compare to other counties in Florida? ▼
Alachua County has 90.1% good air days. Nearby counties in Florida: Baker (69.1% good), Bay (60.6% good), Brevard (89.7% good), Broward (72.4% good), Citrus (67.8% good), Collier (67.4% good).
What is the 90th percentile AQI in Alachua County? ▼
The 90th percentile AQI for Alachua County is 50, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 69 (Moderate).
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.