Cleanest Air Cities in America

US cities ranked by Air Quality Grade, based on 10 years of EPA monitoring data. The grade combines average AQI (40%), trend direction (30%), number of unhealthy days (20%), and the dominant pollutant type (10%).

#1Caguas, Puerto Rico

Median AQI: 65yr Avg: 10↓ Improving

Primary pollutant: NO2

#2Alexandria City, Virginia

Median AQI: 65yr Avg: 6↓ Improving

Primary pollutant: PM10

#3Cook, Minnesota

Median AQI: 135yr Avg: 12↓ Improving

Primary pollutant: PM2.5

#4San Juan, Puerto Rico

Median AQI: 75yr Avg: 10↓ Improving

Primary pollutant: CO

#5Carbon, Wyoming

Median AQI: 85yr Avg: 16↓ Improving

Primary pollutant: Ozone

#6Monroe, Michigan

Median AQI: 255yr Avg: 21↓ Improving

Primary pollutant: PM10

#7Juncos, Puerto Rico

Median AQI: 95yr Avg: 9↓ Improving

Primary pollutant: Ozone

#8Matanuska-Susitna, Alaska

Median AQI: 145yr Avg: 17↓ Improving

Primary pollutant: PM2.5

#9Uinta, Wyoming

Median AQI: 65yr Avg: 21↓ Improving

Primary pollutant: Ozone

#10Adjuntas, Puerto Rico

Median AQI: 145yr Avg: 19↓ Improving

Primary pollutant: PM2.5

#11Hawaii, Hawaii

Median AQI: 235yr Avg: 25↓ Improving

Primary pollutant: PM2.5

#12Rosebud, Montana

Median AQI: 35yr Avg: 23↓ Improving

Primary pollutant: Ozone

#13Luna, New Mexico

Median AQI: 165yr Avg: 17↓ Improving

Primary pollutant: PM10

#14Bayamon, Puerto Rico

Median AQI: 225yr Avg: 18↓ Improving

Primary pollutant: CO

#15Colleton, South Carolina

Median AQI: 265yr Avg: 26↓ Improving

Primary pollutant: PM2.5

#16St Croix, Virgin Islands

Median AQI: 295yr Avg: 27↓ Improving

Primary pollutant: PM2.5

#17Hughes, South Dakota

Median AQI: 145yr Avg: 13↓ Improving

Primary pollutant: PM2.5

#18Humboldt, California

Median AQI: 325yr Avg: 28↓ Improving

Primary pollutant: Ozone

#19Hopewell City, Virginia

Median AQI: 75yr Avg: 7↓ Improving

Primary pollutant: PM10

#20Winchester City, Virginia

Median AQI: 65yr Avg: 7↓ Improving

Primary pollutant: PM10

#21Maui, Hawaii

Median AQI: 205yr Avg: 21↓ Improving

Primary pollutant: PM2.5

#22Cass, Nebraska

Median AQI: 175yr Avg: 16↓ Improving

Primary pollutant: PM10

#23Columbiana, Ohio

Median AQI: 115yr Avg: 12↓ Improving

Primary pollutant: PM10

#24Jefferson, Oregon

Median AQI: 315yr Avg: 28↓ Improving

Primary pollutant: PM2.5

#25Georgetown, South Carolina

Median AQI: 145yr Avg: 14↓ Improving

Primary pollutant: PM10

#26St John, Virgin Islands

Median AQI: 225yr Avg: 21↓ Improving

Primary pollutant: PM2.5

#27Carroll, Virginia

Median AQI: 95yr Avg: 8→ Stable

Primary pollutant: PM10

#28Wyoming, Pennsylvania

Median AQI: 275yr Avg: 33↓ Improving

Primary pollutant: PM2.5

#29Alamosa, Colorado

Median AQI: 225yr Avg: 14↓ Improving

Primary pollutant: PM10

#30Kauai, Hawaii

Median AQI: 135yr Avg: 15↓ Improving

Primary pollutant: PM2.5

#31Floyd, Indiana

Median AQI: 465yr Avg: 36↓ Improving

Primary pollutant: Ozone

#32Jackson, Indiana

Median AQI: 355yr Avg: 35↓ Improving

Primary pollutant: Ozone

#33Taney, Missouri

Median AQI: 295yr Avg: 26↓ Improving

Primary pollutant: PM2.5

#34Jackson, North Carolina

Median AQI: 385yr Avg: 35↓ Improving

Primary pollutant: Ozone

#35Muskogee, Oklahoma

Median AQI: 185yr Avg: 18↓ Improving

Primary pollutant: PM10

#36Windham, Vermont

Median AQI: 145yr Avg: 12↓ Improving

Primary pollutant: PM2.5

#37Anchorage, Alaska

Median AQI: 215yr Avg: 26↓ Improving

Primary pollutant: PM2.5

#38Fremont, Colorado

Median AQI: 125yr Avg: 13→ Stable

Primary pollutant: PM10

#39Morgan, Indiana

Median AQI: 355yr Avg: 35↓ Improving

Primary pollutant: Ozone

#40Douglas, Nevada

Median AQI: 285yr Avg: 22↓ Improving

Primary pollutant: PM2.5

#41Norfolk City, Virginia

Median AQI: 185yr Avg: 18↓ Improving

Primary pollutant: NO2

#42Garfield, Washington

Median AQI: 175yr Avg: 20↓ Improving

Primary pollutant: PM2.5

#43North Slope, Alaska

Median AQI: 45yr Avg: 6↓ Improving

Primary pollutant: PM2.5

#44Tuscaloosa, Alabama

Median AQI: 425yr Avg: 37↓ Improving

Primary pollutant: Ozone

#45Juneau, Alaska

Median AQI: 245yr Avg: 22↓ Improving

Primary pollutant: PM2.5

#46Apache, Arizona

Median AQI: 135yr Avg: 13→ Stable

Primary pollutant: PM10

#47Routt, Colorado

Median AQI: 135yr Avg: 14→ Stable

Primary pollutant: PM10

#48Custer, Idaho

Median AQI: 85yr Avg: 8→ Stable

Primary pollutant: PM2.5

#49Roane, Tennessee

Median AQI: 365yr Avg: 36↓ Improving

Primary pollutant: PM2.5

#50Custer, Oklahoma

Median AQI: 145yr Avg: 14→ Stable

Primary pollutant: PM10

#51Mohave, Arizona

Median AQI: 155yr Avg: 17→ Stable

Primary pollutant: PM10

#52Pitkin, Colorado

Median AQI: 135yr Avg: 13→ Stable

Primary pollutant: PM10

#53Wasco, Oregon

Median AQI: 275yr Avg: 24↓ Improving

Primary pollutant: PM2.5

#54Aleutians East, Alaska

Median AQI: 115yr Avg: 12→ Stable

Primary pollutant: PM2.5

#55Kenai Peninsula, Alaska

Median AQI: 105yr Avg: 10→ Stable

Primary pollutant: PM2.5

#56Napa, California

Median AQI: 415yr Avg: 39↓ Improving

Primary pollutant: PM2.5

#57San Juan, Colorado

Median AQI: 95yr Avg: 9→ Stable

Primary pollutant: PM2.5

#58Charlton, Georgia

Median AQI: 275yr Avg: 26↓ Improving

Primary pollutant: PM2.5

#59Floyd, Georgia

Median AQI: 465yr Avg: 43↓ Improving

Primary pollutant: PM2.5

#60Orleans, Louisiana

Median AQI: 415yr Avg: 36↓ Improving

Primary pollutant: PM2.5

#61Howard, Maryland

Median AQI: 385yr Avg: 37↓ Improving

Primary pollutant: PM2.5

#62Ravalli, Montana

Median AQI: 225yr Avg: 22↓ Improving

Primary pollutant: PM2.5

#63Roosevelt, Montana

Median AQI: 135yr Avg: 14→ Stable

Primary pollutant: PM2.5

#64Scotts Bluff, Nebraska

Median AQI: 215yr Avg: 24↓ Improving

Primary pollutant: PM2.5

#65Socorro, New Mexico

Median AQI: 145yr Avg: 15→ Stable

Primary pollutant: PM2.5

#66Hyde, North Carolina

Median AQI: 265yr Avg: 23↓ Improving

Primary pollutant: PM2.5

#67Martin, North Carolina

Median AQI: 365yr Avg: 35↓ Improving

Primary pollutant: Ozone

#68Mitchell, North Carolina

Median AQI: 335yr Avg: 30↓ Improving

Primary pollutant: PM2.5

#69Athens, Ohio

Median AQI: 315yr Avg: 30↓ Improving

Primary pollutant: PM2.5

#70Guayama, Puerto Rico

Median AQI: 155yr Avg: 24↓ Improving

Primary pollutant: PM2.5

#71Lubbock, Texas

Median AQI: 255yr Avg: 28↓ Improving

Primary pollutant: PM2.5

#72Cowlitz, Washington

Median AQI: 225yr Avg: 22↓ Improving

Primary pollutant: PM2.5

#73Skagit, Washington

Median AQI: 305yr Avg: 28↓ Improving

Primary pollutant: PM2.5

#74Jerome, Idaho

Median AQI: 135yr Avg: 17↓ Improving

Primary pollutant: PM2.5

#75Sherman, Kansas

Median AQI: 195yr Avg: 16→ Stable

Primary pollutant: PM10

#76Pike, Kentucky

Median AQI: 395yr Avg: 39↓ Improving

Primary pollutant: PM2.5

#77Bay, Michigan

Median AQI: 425yr Avg: 32↓ Improving

Primary pollutant: PM2.5

#78Keweenaw, Michigan

Median AQI: 165yr Avg: 13→ Stable

Primary pollutant: PM2.5

#79Winona, Minnesota

Median AQI: 285yr Avg: 23↓ Improving

Primary pollutant: PM2.5

#80Lake, Montana

Median AQI: 135yr Avg: 10→ Stable

Primary pollutant: PM2.5

#81Silver Bow, Montana

Median AQI: 315yr Avg: 27↓ Improving

Primary pollutant: PM2.5

#82Catron, New Mexico

Median AQI: 135yr Avg: 13→ Stable

Primary pollutant: PM2.5

#83Lincoln, New Mexico

Median AQI: 145yr Avg: 14→ Stable

Primary pollutant: PM2.5

#84Mercer, Pennsylvania

Median AQI: 445yr Avg: 42↓ Improving

Primary pollutant: Ozone

#85Monroe, Pennsylvania

Median AQI: 345yr Avg: 35↓ Improving

Primary pollutant: Ozone

#86Montgomery, Tennessee

Median AQI: 365yr Avg: 35↓ Improving

Primary pollutant: PM2.5

#87Wayne, Utah

Median AQI: 125yr Avg: 11→ Stable

Primary pollutant: PM2.5

#88Jefferson, Washington

Median AQI: 215yr Avg: 22↓ Improving

Primary pollutant: PM2.5

#89Marion, West Virginia

Median AQI: 395yr Avg: 38↓ Improving

Primary pollutant: PM2.5

#90Marin, California

Median AQI: 345yr Avg: 36↓ Improving

Primary pollutant: PM2.5

#91Putnam, Florida

Median AQI: 175yr Avg: 16↑ Worsening

Primary pollutant: PM10

#92Honolulu, Hawaii

Median AQI: 315yr Avg: 29↓ Improving

Primary pollutant: Ozone

#93Allen, Indiana

Median AQI: 425yr Avg: 42↓ Improving

Primary pollutant: PM2.5

#94Powell, Montana

Median AQI: 145yr Avg: 11→ Stable

Primary pollutant: PM2.5

#95Thomas, Nebraska

Median AQI: 175yr Avg: 17→ Stable

Primary pollutant: PM2.5

#96Los Alamos, New Mexico

Median AQI: 145yr Avg: 13→ Stable

Primary pollutant: PM2.5

#97Caswell, North Carolina

Median AQI: 365yr Avg: 37↓ Improving

Primary pollutant: Ozone

#98Union, Oregon

Median AQI: 265yr Avg: 27↓ Improving

Primary pollutant: PM2.5

#99Lynchburg City, Virginia

Median AQI: 345yr Avg: 31↓ Improving

Primary pollutant: PM2.5

#100Salem City, Virginia

Median AQI: 365yr Avg: 34↓ Improving

Primary pollutant: PM2.5

#101Adams, Washington

Median AQI: 215yr Avg: 18↓ Improving

Primary pollutant: PM2.5

#102Mason, Washington

Median AQI: 245yr Avg: 24↓ Improving

Primary pollutant: PM2.5

#103Thurston, Washington

Median AQI: 285yr Avg: 27↓ Improving

Primary pollutant: PM2.5

#104Twin Falls, Idaho

Median AQI: 255yr Avg: 27↓ Improving

Primary pollutant: PM2.5

#105Lawrence, Alabama

Median AQI: 345yr Avg: 29↓ Improving

Primary pollutant: PM2.5

#106Prowers, Colorado

Median AQI: 195yr Avg: 17→ Stable

Primary pollutant: PM10

#107Orange, Florida

Median AQI: 435yr Avg: 38↓ Improving

Primary pollutant: Ozone

#108Cobb, Georgia

Median AQI: 435yr Avg: 41↓ Improving

Primary pollutant: Ozone

#109Franklin, Idaho

Median AQI: 245yr Avg: 25↓ Improving

Primary pollutant: PM2.5

#110Carroll, Indiana

Median AQI: 365yr Avg: 34↓ Improving

Primary pollutant: Ozone

#111Posey, Indiana

Median AQI: 385yr Avg: 34↓ Improving

Primary pollutant: Ozone

#112Cerro Gordo, Iowa

Median AQI: 195yr Avg: 18↑ Worsening

Primary pollutant: PM10

#113Androscoggin, Maine

Median AQI: 355yr Avg: 34↓ Improving

Primary pollutant: PM2.5

#114Sheridan, Montana

Median AQI: 185yr Avg: 16→ Stable

Primary pollutant: PM2.5

#115Oneida, New York

Median AQI: 325yr Avg: 25↓ Improving

Primary pollutant: PM2.5

#116Clermont, Ohio

Median AQI: 415yr Avg: 42↓ Improving

Primary pollutant: PM2.5

#117Westmoreland, Pennsylvania

Median AQI: 425yr Avg: 42↓ Improving

Primary pollutant: PM2.5

#118Lawrence, Tennessee

Median AQI: 415yr Avg: 33↓ Improving

Primary pollutant: PM2.5

#119Maury, Tennessee

Median AQI: 365yr Avg: 33↓ Improving

Primary pollutant: PM2.5

#120Putnam, Tennessee

Median AQI: 385yr Avg: 34↓ Improving

Primary pollutant: PM2.5

#121Fayette, Texas

Median AQI: 345yr Avg: 34↓ Improving

Primary pollutant: PM2.5

#122Maverick, Texas

Median AQI: 345yr Avg: 35↓ Improving

Primary pollutant: PM2.5

#123Grays Harbor, Washington

Median AQI: 235yr Avg: 25↓ Improving

Primary pollutant: PM2.5

#124Lewis, Washington

Median AQI: 255yr Avg: 25↓ Improving

Primary pollutant: PM2.5

#125Brooke, West Virginia

Median AQI: 195yr Avg: 19→ Stable

Primary pollutant: PM10

#126Platte, Wyoming

Median AQI: 145yr Avg: 16→ Stable

Primary pollutant: PM10

#127Clay, Alabama

Median AQI: 415yr Avg: 37↓ Improving

Primary pollutant: PM2.5

#128Boone, Indiana

Median AQI: 375yr Avg: 35↓ Improving

Primary pollutant: Ozone

#129Huntington, Indiana

Median AQI: 315yr Avg: 31↓ Improving

Primary pollutant: Ozone

#130Perry, Indiana

Median AQI: 385yr Avg: 36↓ Improving

Primary pollutant: Ozone

#131Warrick, Indiana

Median AQI: 385yr Avg: 36↓ Improving

Primary pollutant: Ozone

#132Ford, Kansas

Median AQI: 155yr Avg: 15↑ Worsening

Primary pollutant: PM10

#133Aroostook, Maine

Median AQI: 375yr Avg: 36↓ Improving

Primary pollutant: PM2.5

#134Penobscot, Maine

Median AQI: 355yr Avg: 33↓ Improving

Primary pollutant: PM2.5

#135Prince George's, Maryland

Median AQI: 445yr Avg: 42↓ Improving

Primary pollutant: Ozone

#136Suffolk, Massachusetts

Median AQI: 445yr Avg: 44↓ Improving

Primary pollutant: PM2.5

#137Washington, Minnesota

Median AQI: 425yr Avg: 37↓ Improving

Primary pollutant: Ozone

#138Stoddard, Missouri

Median AQI: 375yr Avg: 31↓ Improving

Primary pollutant: PM2.5

#139Sarpy, Nebraska

Median AQI: 375yr Avg: 38↓ Improving

Primary pollutant: PM2.5

#140Washington, Nebraska

Median AQI: 335yr Avg: 31↓ Improving

Primary pollutant: PM2.5

#141Herkimer, New York

Median AQI: 295yr Avg: 29↓ Improving

Primary pollutant: Ozone

#142Deschutes, Oregon

Median AQI: 285yr Avg: 25↓ Improving

Primary pollutant: PM2.5

#143Bucks, Pennsylvania

Median AQI: 395yr Avg: 37↓ Improving

Primary pollutant: Ozone

#144Erie, Pennsylvania

Median AQI: 425yr Avg: 39↓ Improving

Primary pollutant: PM2.5

#145Oconee, South Carolina

Median AQI: 375yr Avg: 37↓ Improving

Primary pollutant: Ozone

#146Brown, South Dakota

Median AQI: 295yr Avg: 26↓ Improving

Primary pollutant: PM2.5

#147Bristol City, Virginia

Median AQI: 395yr Avg: 35↓ Improving

Primary pollutant: PM2.5

#148Harrison, West Virginia

Median AQI: 395yr Avg: 37↓ Improving

Primary pollutant: PM2.5

#149Park, Wyoming

Median AQI: 145yr Avg: 20→ Stable

Primary pollutant: PM2.5

#150Lake, California

Median AQI: 325yr Avg: 32↓ Improving

Primary pollutant: Ozone

#151Columbia, Georgia

Median AQI: 365yr Avg: 35↓ Improving

Primary pollutant: Ozone

#152Clark, Illinois

Median AQI: 365yr Avg: 34↓ Improving

Primary pollutant: Ozone

#153Macoupin, Illinois

Median AQI: 375yr Avg: 33↓ Improving

Primary pollutant: Ozone

#154Shelby, Indiana

Median AQI: 375yr Avg: 35↓ Improving

Primary pollutant: Ozone

#155Chase, Kansas

Median AQI: 295yr Avg: 26→ Stable

Primary pollutant: PM2.5

#156Rockingham, New Hampshire

Median AQI: 405yr Avg: 40↓ Improving

Primary pollutant: Ozone

#157Chaves, New Mexico

Median AQI: 245yr Avg: 24→ Stable

Primary pollutant: PM2.5

#158Nassau, New York

Median AQI: 315yr Avg: 30↓ Improving

Primary pollutant: PM2.5

#159Ellis, Texas

Median AQI: 365yr Avg: 41↓ Improving

Primary pollutant: PM2.5

#160Box Elder, Utah

Median AQI: 385yr Avg: 39↓ Improving

Primary pollutant: Ozone

#161Garfield, Utah

Median AQI: 105yr Avg: 36↓ Improving

Primary pollutant: Ozone

#162Stafford, Virginia

Median AQI: 375yr Avg: 36↓ Improving

Primary pollutant: Ozone

#163Franklin, Washington

Median AQI: 265yr Avg: 22→ Stable

Primary pollutant: PM2.5

#164Klickitat, Washington

Median AQI: 205yr Avg: 22→ Stable

Primary pollutant: PM2.5

#165Whatcom, Washington

Median AQI: 315yr Avg: 29↓ Improving

Primary pollutant: PM2.5

#166Belmont, Ohio

Median AQI: 315yr Avg: 18↑ Worsening

Primary pollutant: NO2

#167Northampton, North Carolina

Median AQI: 375yr Avg: 35↓ Improving

Primary pollutant: PM2.5

#168San Mateo, California

Median AQI: 315yr Avg: 36↓ Improving

Primary pollutant: PM2.5

#169Coffee, Georgia

Median AQI: 415yr Avg: 36↓ Improving

Primary pollutant: PM2.5

#170Brown, Indiana

Median AQI: 375yr Avg: 35↓ Improving

Primary pollutant: Ozone

#171Elkhart, Indiana

Median AQI: 445yr Avg: 43↓ Improving

Primary pollutant: PM2.5

#172Kent, Maryland

Median AQI: 415yr Avg: 40↓ Improving

Primary pollutant: Ozone

#173Carlton, Minnesota

Median AQI: 385yr Avg: 29→ Stable

Primary pollutant: Ozone

#174Orange, New York

Median AQI: 345yr Avg: 37↓ Improving

Primary pollutant: Ozone

#175Greene, Ohio

Median AQI: 445yr Avg: 41↓ Improving

Primary pollutant: PM2.5

#176Clearfield, Pennsylvania

Median AQI: 355yr Avg: 33↓ Improving

Primary pollutant: Ozone

#177Northampton, Pennsylvania

Median AQI: 465yr Avg: 44↓ Improving

Primary pollutant: PM2.5

#178Chesterfield, South Carolina

Median AQI: 425yr Avg: 39↓ Improving

Primary pollutant: PM2.5

#179Ector, Texas

Median AQI: 335yr Avg: 36↓ Improving

Primary pollutant: PM2.5

#180Potter, Texas

Median AQI: 265yr Avg: 28→ Stable

Primary pollutant: PM2.5

#181Rockwall, Texas

Median AQI: 345yr Avg: 33↓ Improving

Primary pollutant: Ozone

#182Whitman, Washington

Median AQI: 265yr Avg: 23→ Stable

Primary pollutant: PM2.5

#183Kootenai, Idaho

Median AQI: 325yr Avg: 30↓ Improving

Primary pollutant: PM2.5

#184Sumter, Alabama

Median AQI: 355yr Avg: 36↓ Improving

Primary pollutant: PM2.5

#185Amador, California

Median AQI: 365yr Avg: 37↓ Improving

Primary pollutant: Ozone

#186Sonoma, California

Median AQI: 335yr Avg: 36↓ Improving

Primary pollutant: Ozone

#187Jackson, Colorado

Median AQI: 455yr Avg: 21↑ Worsening

Primary pollutant: PM2.5

#188Hartford, Connecticut

Median AQI: 435yr Avg: 42↓ Improving

Primary pollutant: PM2.5

#189Indian River, Florida

Median AQI: 345yr Avg: 35↓ Improving

Primary pollutant: Ozone

#190Manatee, Florida

Median AQI: 355yr Avg: 34→ Stable

Primary pollutant: Ozone

#191Nassau, Florida

Median AQI: 425yr Avg: 42↓ Improving

Primary pollutant: PM2.5

#192Hendricks, Indiana

Median AQI: 375yr Avg: 34↓ Improving

Primary pollutant: Ozone

#193Howard, Indiana

Median AQI: 455yr Avg: 44↓ Improving

Primary pollutant: PM2.5

#194Hardin, Kentucky

Median AQI: 455yr Avg: 44↓ Improving

Primary pollutant: PM2.5

#195Ascension, Louisiana

Median AQI: 345yr Avg: 32→ Stable

Primary pollutant: Ozone

#196Rapides, Louisiana

Median AQI: 435yr Avg: 39↓ Improving

Primary pollutant: PM2.5

#197St. James, Louisiana

Median AQI: 335yr Avg: 30→ Stable

Primary pollutant: Ozone

#198Baltimore (City), Maryland

Median AQI: 445yr Avg: 43↓ Improving

Primary pollutant: PM2.5

#199Calvert, Maryland

Median AQI: 425yr Avg: 39↓ Improving

Primary pollutant: Ozone

#200Garrett, Maryland

Median AQI: 405yr Avg: 39↓ Improving

Primary pollutant: Ozone