Air Quality by State
Browse comprehensive air quality data for all 51 US states and territories. Each state page provides detailed city-by-city AQI information, regional air quality patterns, and health recommendations based on official EPA data.
States with Cleanest Air
View all cleanest citiesStates Requiring More Attention
View all areas of concernProtect Your Indoor Air in Montana
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All States
Alabama
AQI 43Alaska
AQI 35Arizona
AQI 79Arkansas
AQI 53California
AQI 58Colorado
AQI 62Connecticut
AQI 51Delaware
AQI 49District of Columbia
AQI 53Florida
AQI 30Georgia
AQI 40Hawaii
AQI 19Idaho
AQI 101Illinois
AQI 52Indiana
AQI 64Iowa
AQI 42Kansas
AQI 53Kentucky
AQI 51Louisiana
AQI 47Maine
AQI 65Maryland
AQI 50Massachusetts
AQI 37Michigan
AQI 43Minnesota
AQI 32Mississippi
AQI 33Missouri
AQI 60Montana
AQI 129Nebraska
AQI 40Nevada
AQI 69New Hampshire
AQI 37New Jersey
AQI 53New Mexico
AQI 49New York
AQI 51North Carolina
AQI 40North Dakota
AQI 26Ohio
AQI 61Oklahoma
AQI 52Oregon
AQI 33Pennsylvania
AQI 56Rhode Island
AQI 52South Carolina
AQI 22South Dakota
AQI 20Tennessee
AQI 44Texas
AQI 42Utah
AQI 74Vermont
AQI 39Virginia
AQI 51Washington
AQI 73West Virginia
No dataWisconsin
AQI 33Wyoming
AQI 76Understanding State Air Quality Data
Air quality varies significantly across different states due to a combination of geographic, climatic, economic, and demographic factors. Understanding these variations helps you make informed decisions about outdoor activities, travel, and relocation.
Factors Affecting State Air Quality
- Population density: More people typically means more vehicle emissions and energy consumption
- Industrial activity: Manufacturing, power generation, and mining contribute to local pollution
- Geography: Valleys and basins can trap pollution, while coastal areas often have cleaner air
- Climate: Hot, sunny weather increases ozone formation; temperature inversions trap pollutants
- Wildfire risk: Western states face seasonal smoke impacts from wildfires
How to Use This Data
- Click any state to see detailed city-level air quality data
- Compare states when planning relocation or extended travel
- State averages represent typical conditions; check specific cities for detailed data
- Consider seasonal variations when comparing long-term air quality
The average AQI shown for each state is calculated from all monitored cities within that state. Air quality can vary significantly within a state, so we recommend checking individual city pages for the most accurate local information.
Official EPA Data
All air quality data comes directly from the EPA's official monitoring network.