IN · GEOID 18115

Ohio County area

Ohio County, Indiana covers 87.5 square miles: 86.2 square miles of land and 1.3 square miles of water.

Official Census measurements2026 Gazetteer · retrieved September 27, 2026
Land area86.2 mi²
Water area1.3 mi²
Total area87.5 mi²
National land rank#3094

County outline

Generalized outline of Ohio County, Indiana
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Ohio County is located

Ohio County highlighted on a map of all U.S. county equivalents. About the maps

Area breakdown

Land accounts for 98.5% of Ohio County’s measured area and water for 1.5%. Its combined area converts to 226.5 square kilometers or approximately 55,969 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land86.15223.12755,136
Water1.3013.37832.6
Total87.451226.49755,968.6

How Ohio County compares

By original Census land area, Ohio County ranks #92 of 92 in Indiana and #3094 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.217 times the Indiana county-equivalent median of 396.4 square miles. It accounts for 0.2% of the combined county land area in the state.

See the complete Indiana ranking · What counts as a county equivalent?

What stands out about Ohio County?

Ohio County has more land than 128 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Ohio County86.2 mi²
Indiana median396.4 mi²
National median604.5 mi²

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 Ohio County at #3,118 nationally by total area, 24 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 1.5%, compared with a national county-equivalent median of 1.2% — 0.3 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 Ohio County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#3093Brooke County, West Virginia89Compare
#3094Ohio County, Indiana86.2This county
#3095Mathews County, Virginia85.9Compare

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 38.940527, -84.964299. 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: 223,126,827 m²; AWATER: 3,369,531 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How many acres of land are in Ohio County?

The land measurement converts to approximately 55,136 acres. Including water, total area is approximately 55,969 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.

Cite this county

Download the complete CSV or JSON dataset