IN · GEOID 18033

DeKalb County area

DeKalb County, Indiana covers 363.9 square miles: 362.8 square miles of land and 1 square miles of water.

Official Census measurements2026 Gazetteer · retrieved September 27, 2026
Land area362.8 mi²
Water area1 mi²
Total area363.9 mi²
National land rank#2646

County outline

Generalized outline of DeKalb 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 DeKalb County is located

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

Area breakdown

Land accounts for 99.7% of DeKalb County’s measured area and water for 0.3%. Its combined area converts to 942.4 square kilometers or approximately 232,870 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land362.834939.736232,213.8
Water1.0262.657656.6
Total363.86942.393232,870.4

How DeKalb County compares

By original Census land area, DeKalb County ranks #68 of 92 in Indiana and #2646 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.915 times the Indiana county-equivalent median of 396.4 square miles. It accounts for 1% of the combined county land area in the state.

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

What stands out about DeKalb County?

DeKalb County has more land than 576 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
DeKalb County362.8 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 DeKalb County at #2,697 nationally by total area, 51 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 0.3%, compared with a national county-equivalent median of 1.2% — 0.9 percentage points lower. 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 DeKalb County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2645Arenac County, Michigan363.2Compare
#2646DeKalb County, Indiana362.8This county
#2647Lebanon County, Pennsylvania361.8Compare

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 41.396760, -85.002697. 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: 939,735,805 m²; AWATER: 2,657,420 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 DeKalb County?

The land measurement converts to approximately 232,214 acres. Including water, total area is approximately 232,870 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