County research and study

Find a county. Start with the facts.

3,144 counties and county equivalents across the 50 states and D.C., plus 78 Puerto Rico municipios. Search names or FIPS codes, compare Census geography and keep the original sources with your work.

• Alabama

  67 counties and equivalents

• Alaska

  30 counties and equivalents

• Arizona

  15 counties and equivalents

• Arkansas

  75 counties and equivalents

• California

  58 counties and equivalents

• Colorado

  64 counties and equivalents

• Connecticut

  9 counties and equivalents

• Delaware

  3 counties and equivalents

• District of Columbia

  1 counties and equivalents

• Florida

  67 counties and equivalents

• Georgia

  159 counties and equivalents

• Hawaii

  5 counties and equivalents

• Idaho

  44 counties and equivalents

• Illinois

  102 counties and equivalents

• Indiana

  92 counties and equivalents

• Iowa

  99 counties and equivalents

• Kansas

  105 counties and equivalents

• Kentucky

  120 counties and equivalents

• Louisiana

  64 counties and equivalents

• Maine

  16 counties and equivalents

• Maryland

  24 counties and equivalents

• Massachusetts

  14 counties and equivalents

• Michigan

  83 counties and equivalents

• Minnesota

  87 counties and equivalents

• Mississippi

  82 counties and equivalents

• Missouri

  115 counties and equivalents

• Montana

  56 counties and equivalents

• Nebraska

  93 counties and equivalents

• Nevada

  17 counties and equivalents

• New Hampshire

  10 counties and equivalents

• New Jersey

  21 counties and equivalents

• New Mexico

  33 counties and equivalents

• New York

  62 counties and equivalents

• North Carolina

  100 counties and equivalents

• North Dakota

  53 counties and equivalents

• Ohio

  88 counties and equivalents

• Oklahoma

  77 counties and equivalents

• Oregon

  36 counties and equivalents

• Pennsylvania

  67 counties and equivalents

• Puerto Rico

  78 counties and equivalents

• Rhode Island

  5 counties and equivalents

• South Carolina

  46 counties and equivalents

• South Dakota

  66 counties and equivalents

• Tennessee

  95 counties and equivalents

• Texas

  254 counties and equivalents

• Utah

  29 counties and equivalents

• Vermont

  14 counties and equivalents

• Virginia

  133 counties and equivalents

• Washington

  39 counties and equivalents

• West Virginia

  55 counties and equivalents

• Wisconsin

  72 counties and equivalents

• Wyoming

  23 counties and equivalents

Use the county data

Use a county profile as a source-reading exercise or the geographic context for your own research. Keep the county FIPS identifier with your notes so that similarly named places in different states are not mixed.

The figures describe the county; they are not an evaluation of schools or an estimate of educational outcomes.

Geography: 2025 U.S. Census Gazetteer. Population: Vintage 2025 estimates, July 1, 2025. County equivalents include parishes, boroughs, independent cities and planning regions. Puerto Rico population is not supplied by this population file.