Which county in Florida has the best air quality?

Based on 2024 EPA AQS data, Putnam County had the best air quality in Florida with a median AQI of 25 and 329 good-air days.

2024 monitoring year Public dataset EPA AQS

Florida Air Quality Rankings

Compiled by PlainEnviro Editorial, Environmental Data Editorial Team · July 13, 2026

County-level AQI rollup using EPA Air Quality System monitor records. Refreshed as new EPA AQS data lands.

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County-by-county air quality data for Florida based on EPA AQS annual AQI readings. Data covers 39 monitored counties for 2024.

Florida (2024): 39 counties monitored. State average median AQI: 41 (national average: 38.8). 77% of monitored days rated "Good." Most unhealthy air: Miami-dade County (3 days above AQI 100).

Florida air quality on this page is drawn from the EPA Air Quality System (AQS), which aggregates daily readings from federal, state, tribal, and local monitors into annual summaries per county. The current dataset covers 39 Florida counties with at least ten days of valid AQI readings in 2024, out of the state's total monitored counties.

The state-average median AQI across those counties is 41, compared with a national average of 38.8 in the same reporting period. On average, 77% of monitored days fell into the "Good" AQI bucket (0–50). The heaviest burden of unhealthy days lands on Miami-dade County (3 days above AQI 100), while Putnam County records the cleanest air with a median AQI of 25.

AQI values translate ambient concentrations of pollutants (ozone, PM2.5, PM10, NO₂, SO₂, CO) onto a single 0–500 scale with six health-based bands. A low median AQI reflects typical daily conditions; peak values matter separately because short-term exposure drives most acute health effects. Counties without monitors are not "clean" - they are simply unmeasured by EPA AQS. For site-specific exposure guidance, check AirNow.gov alongside the county detail links below.

Counties with Data

State Avg Median AQI

National Avg Median AQI

38.8

Avg Good Days %

77%

Which Florida counties have the worst air quality?

Ranked by median AQI (higher = worse). Click a county for full environmental data.

#	County	Median AQI	Good Days	Good %	Unhealthy Days	Peak AQI
1	Duval	50	190	52%	0	98
2	Hillsborough	50	190	52%	0	143
3	Marion	49	189	53%	0	101
4	Miami-dade	48	219	60%	3	197
5	Pinellas	48	213	59%	0	132
6	Bay	47	214	60%	1	215
7	Holmes	47	215	60%	0	73
8	Broward	47	213	58%	1	154
9	Santa Rosa	46	235	64%	0	81
10	Columbia	44	220	63%	0	93
11	Hamilton	44	215	67%	0	75
12	Leon	44	243	68%	0	129
13	Sarasota	44	242	67%	0	115
14	Escambia	43	256	70%	0	84
15	Seminole	43	204	71%	0	149
16	Palm Beach	43	257	70%	0	76
17	Citrus	43	248	72%	1	272
18	Nassau	42	35	81%	0	57
19	Baker	42	279	78%	0	87
20	Collier	42	279	76%	0	87
21	Wakulla	41	261	73%	0	139
22	Orange	41	272	76%	0	121
23	Brevard	40	311	85%	0	74
24	Volusia	39	293	81%	0	76
25	Pasco	39	320	90%	0	97
26	Polk	39	282	77%	0	105
27	Martin	39	309	87%	0	71
28	Alachua	38	300	86%	0	94
29	Lee	37	313	92%	0	80
30	Manatee	37	317	91%	0	115
31	Okaloosa	36	341	93%	0	74
32	Lake	36	312	91%	0	100
33	Osceola	36	314	90%	0	108
34	Flagler	35	344	97%	0	71
35	Indian River	35	344	99%	0	64
36	St Lucie	35	353	98%	0	64
37	Highlands	35	333	92%	0	77
38	Liberty	31	327	99%	0	54
39	Putnam	25	329	91%	0	112

Frequently Asked Questions

What is the air quality like in Florida?

In 2024, Florida had an average median AQI of 41 across 39 monitored counties, with 77% of monitored days rated "Good" (AQI 0–50). The national average median AQI is 38.8.

Which county in Florida has the worst air quality?

Based on 2024 EPA AQS data, Miami-dade County had the most unhealthy air days in Florida - 3 days above AQI 100, with a median AQI of 48.

Explore More

National AQI Rankings → Florida Full Profile → Florida Water Quality →

About This Data

Air quality data is from the EPA Air Quality System (AQS), Annual AQI by County dataset. Counties with fewer than 10 monitored days are excluded. "Unhealthy days" counts days with AQI above 100 (Unhealthy for Sensitive Groups or worse). All data is for 2024.

Source: U.S. Environmental Protection Agency, Air Quality System (AQS) U.S. Environmental Protection Agency, Air Quality System (AQS)

Read our methodology - how this data is sourced, computed, and verified.

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Data sourced from the U.S. Environmental Protection Agency (EPA). See our methodology for details. Retrieved and formatted by PlainEnviro Editorial