Ohio Counties, Demographics & Geography
Complete official guide to all 88 counties in Ohio (OH). Explore 2024 US Census population estimates, county seats, FIPS codes, land areas, and interactive mapping tools powered by GeoMap Suite.
Ohio County Breakdown
Showing 9 of 9 documented counties and seats.
County Name | FIPS | County Seat | Population (Census) | Land Area | Quick Tool |
|---|---|---|---|---|---|
| Franklin County (Columbus) | 39049 | Columbus | 1,323,807 | 532 sq mi | Lookup |
| Cuyahoga County (Cleveland) | 39035 | Cleveland | 1,264,817 | 457 sq mi | Lookup |
| Hamilton County (Cincinnati) | 39061 | Cincinnati | 830,639 | 406 sq mi | Lookup |
| Summit County (Akron) | 39153 | Akron | 540,428 | 413 sq mi | Lookup |
| Montgomery County (Dayton) | 39113 | Dayton | 537,309 | 462 sq mi | Lookup |
| Lucas County (Toledo) | 39095 | Toledo | 431,279 | 341 sq mi | Lookup |
| Butler County | 39017 | Hamilton | 390,357 | 467 sq mi | Lookup |
| Stark County (Canton) | 39151 | Canton | 374,853 | 576 sq mi | Lookup |
| Lorain County | 39093 | Elyria | 312,964 | 491 sq mi | Lookup |
Geographic Structure of Ohio Counties
County Administration & Governance
In Ohio, county governments manage vital public infrastructure, tax assessments, law enforcement, judicial courts, election administration, and public records. The county seat (Columbus and other municipal headquarters) houses the primary courthouse, commissioners, and sheriff’s department.
All Ohio counties carry a unique 5-digit Federal Information Processing Standard (FIPS) code, where the first two digits (39) designate the state and the remaining three digits identify each specific jurisdiction.
Geographic & Demographic Highlights
- Most Populous County:Franklin County (Columbus) (1,323,807 residents)
- Largest by Land Area:Stark County (Canton) (576 sq mi)
- State Capital:Columbus
- Census Bureau Region:Midwest United States
Demographic calculations derive from the United States Census Bureau 2024 Population Estimates Program (PEP) and TIGER/Line geographic boundary files.