THE DEKALB COUNTY LAND BRIEF
Land in the
Illinois/Indiana Prairies setting.
DeKalb County has 631.3 square miles of land in Illinois. The mapped landscape region in DeKalb County is Illinois/Indiana Prairies.
Glaciated plains historically supported tallgrass prairie mixed with oak and hickory woodland. Dark prairie soils and broad farming landscapes distinguish much of the Central Corn Belt.
Regional context: Central Corn Belt Plains ↗ · Regional mapping across the county footprint
Finding your parcel within DeKalb County
The atlas lists 33 cities, towns, townships, and Census communities associated with DeKalb County, including Paw Paw, Genoa, Franklin. The list includes overlapping geography types and does not divide the county into exclusive service areas.
DeKalb County by land and water
The Census records 3.31 square miles of water within DeKalb County, or 0.5% of its total area. That share is close to DeKalb County’s 0.5%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, DeKalb County has 35.4 times the land area of nearby DeKalb city (17.8 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Boone County, Kane County, Kendall County, LaSalle County, Lee County, McHenry County, Ogle County, Winnebago County within Illinois. A tract near one of these lines should be matched to the county identifier on its own records.

