County outline
Where Franklin County is located
Area breakdown
Land accounts for 97.9% of Franklin County’s measured area and water for 2.1%. Its combined area converts to 1,408 square kilometers or approximately 347,917 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 532.432 | 1,378.993 | 340,756.5 |
| Water | 11.189 | 28.979 | 7,161 |
| Total | 543.621 | 1,407.972 | 347,917.4 |
How Franklin County compares
By original Census land area, Franklin County ranks #17 of 88 in Ohio and #1960 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 1.221 times the Ohio county-equivalent median of 436 square miles. It accounts for 1.3% of the combined county land area in the state.
See the complete Ohio ranking · What counts as a county equivalent?
Population and density of Franklin County
The Census Bureau estimates that 1,361,536 people lived in Franklin County on July 1, 2025. That ranks #32 of 3,222 county equivalents nationally and #1 of 88 in Ohio. Since the April 1, 2020 estimates base of 1,323,793, the population has grown by 37,743 (+2.9%), compared with +0.9% for Ohio as a whole.
With 532.4 square miles of land, that is 2,557 people per square mile (987 per km²), placing Franklin County #57 nationally for density and #2 in Ohio. The median county equivalent has 47 people per square mile; the Ohio median is 120. Put another way, there are about 0.25 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 1,324,478 | 1,317,228 | 1,326,392 | 1,337,095 | 1,352,656 | 1,361,536 |
| Change | — | −7,250 | +9,164 | +10,703 | +15,561 | +8,880 |
U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.
Cities and towns in Franklin County
27 incorporated places lie at least partly in Franklin County. Together they are home to 1,262,158 people (92.7%); the other 99,378 (7.3%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Columbus city, with 911,199 residents in the county (the city extends into 2 other counties). Among places with at least 1,000 residents in 2020, Obetz city grew fastest since then (+33.9%).
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Columbus cityCounty seat · Also in 2 other counties | 911,199 | +3.5% | 222.9 |
| Grove City city | 45,180 | +9.5% | 19 |
| Dublin cityAlso in 2 other counties | 40,613 | −0.3% | 25.1 |
| Hilliard city | 38,898 | +4.7% | 14.2 |
| Gahanna city | 35,986 | +0.7% | 12.4 |
| Upper Arlington city | 35,893 | −2.4% | 9.807 |
| Reynoldsburg cityAlso in 2 other counties | 31,016 | +4.3% | 11.3 |
| Westerville cityAlso in 1 other county | 29,046 | −3.1% | 12.6 |
| Whitehall city | 19,805 | −1.6% | 5.286 |
| Worthington city | 14,543 | −1.6% | 5.473 |
| Bexley city | 12,452 | −10.6% | 2.421 |
| New Albany cityAlso in 1 other county | 11,399 | +5.6% | 21.9 |
| Grandview Heights city | 9,112 | +12.7% | 1.316 |
| Canal Winchester cityAlso in 1 other county | 8,250 | +11.3% | 8.297 |
| Obetz city | 7,342 | +33.9% | 5.825 |
Show the other 12 places
| Name | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Groveport city | 5,818 | −3.2% | 8.786 |
| Minerva Park village | 1,950 | −3.1% | 0.647 |
| Urbancrest village | 1,003 | −3.1% | 0.587 |
| Marble Cliff village | 658 | +3.1% | 0.281 |
| Valleyview village | 640 | −2.9% | 0.143 |
| Riverlea village | 578 | −3.2% | 0.151 |
| Harrisburg villageAlso in 1 other county | 313 | −0.3% | 0.155 |
| Lockbourne villageAlso in 1 other county | 228 | −3.8% | 0.797 |
| Brice village | 110 | +17% | 0.088 |
| Pickerington cityAlso in 1 other county | 77 | +10% | 10.4 |
| Lithopolis villageAlso in 1 other county | 49 | −2% | 2.269 |
| Commercial Point villageAlso in 1 other county | 0 | — | 4.687 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Franklin County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Franklin County is a central county of the Columbus, OH Metropolitan Statistical Area. Its 10 county equivalents have 2,242,028 residents on 4,797.5 square miles of land; Franklin County accounts for 11.1% of the land and 60.7% of the residents. By combined land it ranks #55 of 393 metropolitan areas, and #32 by population. It belongs to the Columbus-Marion-Zanesville, OH Combined Statistical Area.
| County equivalent | Population 2025 | Land mi² |
|---|---|---|
| Franklin County | 1,361,536 | 532.4 |
| Delaware County | 242,032 | 443.1 |
| Licking County | 185,564 | 682.4 |
| Fairfield County | 169,752 | 504.4 |
| Union County | 73,446 | 431.7 |
| Pickaway County | 62,978 | 501.3 |
| Madison County | 46,985 | 466.7 |
| Morrow County | 36,305 | 406.1 |
| Perry County | 35,918 | 407.9 |
| Hocking County | 27,512 | 421.4 |
ZIP codes
50 ZIP Code Tabulation Areas have land in Franklin County; 42 of them have most of their land inside the county, and the others mainly cover neighboring areas.
4300243004430164301743026430544306443065430684308143085431094311043119431234312543126431374314043146431474320143202432034320443205432064320743209432104321143212432134321443215432174321843219432204322143222432234322443227432284322943230432314323243235
ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.
Counties bordering Franklin County
Franklin County shares a land border with 6 county equivalents. It has more land than 5 of them. The largest neighbor is Licking County (682.4 mi²) and the smallest is Union County (431.7 mi²). Together with its neighbors, Franklin County forms a block of 3,562 mi² of land, of which it holds 14.9%.
| Bordering county equivalent | Land mi² | Size vs. Franklin | Compare |
|---|---|---|---|
| Licking County | 682.4 | 1.3× larger | Compare |
| Fairfield County | 504.4 | 1.1× smaller | Compare |
| Pickaway County | 501.3 | 1.1× smaller | Compare |
| Madison County | 466.7 | 1.1× smaller | Compare |
| Delaware County | 443.1 | 1.2× smaller | Compare |
| Union County | 431.7 | 1.2× smaller | Compare |
How big is Franklin County compared with U.S. states?
Franklin County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.9 times as much. Ohio’s county land could hold about 77 areas the size of Franklin County.
Another way to picture it: the same land area would fill a square about 23.1 miles (37.1 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.
State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.
What stands out about Franklin County?
Franklin County has more land than 1,262 of the other 3,221 county equivalents in the dataset.
A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.
Does including water change its rank?
Using land plus water places Franklin County at #2,026 nationally by total area, 66 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.
Its water share is 2.1%, compared with a national county-equivalent median of 1.2% — 0.9 percentage points higher. This describes the statistical geography’s land/water mix, not flood exposure or developable land.
Closest positions in the national land ranking
These entries sit immediately beside Franklin County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #1959 | Jefferson County, Kansas | 532.6 | Compare |
| #1960 | Franklin County, Ohio | 532.4 | This county |
| #1961 | Livingston County, Missouri | 532.3 | Compare |
Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.
Representative coordinates
The Census internal point is 39.969875, -83.009086. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.
Source and precision
U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 1,378,992,893 m²; AWATER: 28,978,544 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.
Common questions
How big is Franklin County?
Franklin County, Ohio has 532.4 square miles (1,379 km²) of land and 11.2 square miles of water, for a total area of 543.6 square miles. It ranks #1960 of 3,222 U.S. county equivalents by land area.
Is Franklin County the largest county in Ohio?
No. Franklin County ranks #17 of 88 in Ohio by land area. The largest is Ashtabula County, with 702.4 square miles of land.
What counties border Franklin County?
Franklin County shares a land border with Pickaway County, Delaware County, Madison County, Licking County, Fairfield County, and Union County.
What is the population of Franklin County?
The Census Bureau estimates Franklin County had 1,361,536 residents on July 1, 2025, ranking #32 of 3,222 county equivalents. That is 2,557 people per square mile of land.
What is the county seat of Franklin County?
The county seat of Franklin County is Columbus.
What cities and towns are in Franklin County?
Franklin County has 27 incorporated places. The most populous five are Columbus city, Grove City city, Dublin city, Hilliard city, and Gahanna city; 99,378 residents live outside any incorporated place.
Is Franklin County part of a metropolitan area?
Yes. It is a central county of the Columbus, OH Metropolitan Statistical Area, which has 10 county equivalents and 2,242,028 residents.
How many ZIP codes are in Franklin County?
50 ZIP Code Tabulation Areas have land in Franklin County, and 42 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Franklin County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 1.9 times as much land.
How many acres of land are in Franklin County?
The land measurement converts to approximately 340,756 acres. Including water, total area is approximately 347,917 acres. One square mile equals 640 acres.
Why might another source show a different area?
Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.
Can this establish a property boundary?
No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.