Illinois · FIPS 17037 · County seat: Sycamore
DeKalb County, IL GIS & Parcel Viewer
DeKalb County, Illinois parcel data lives on DeKalb County GIS Web Base. Open it below in a new tab, then use the short steps on this page to find a property fast.
Open the DeKalb County parcel map ↗
Opens spatial.dekalbcounty.org in a new tab. We link out and never embed or copy parcel data.
DeKalb County at a glance
| Official map | DeKalb County GIS Web Base |
|---|---|
| Type | County-run map |
| Website | spatial.dekalbcounty.org |
| Access | Free, no login (checked Oct 2026) |
| County seat | Sycamore |
| Population | 100,288 (2023 Census Bureau estimate) |
| Land area | 631 sq mi |
| FIPS code | 17037 |
About the official source
DeKalb County runs this viewer (directly or through a contracted vendor), which makes it the closest thing to the source for local parcel lines. Our October 2026 check found the map open to the public, with no account or payment needed.
Searching for a parcel, step by step
- Open the official link in a new tab.
- Accept any disclaimer, then look for a search box that takes street addresses, owners or parcel IDs.
- Zoom in and click a parcel to see its details.
- Use the map's layer controls to add aerials or other layers if they're offered.
Have a tax bill handy? The parcel or account number on it is usually the fastest way to search.
About DeKalb County
The U.S. Census Bureau estimated DeKalb County's population at 100,288 in 2023, spread over about 631 square miles of land, or roughly 159 people per square mile. Among Illinois's 102 counties, it is the 20th largest by population. The county seat is Sycamore.
Neighboring counties
DeKalb County shares a border with the counties below. Each link has its own official map:
- Boone County
- Kane County
- Kendall County
- LaSalle County
- Lee County
- McHenry County
- Ogle County
- Winnebago County
Before you rely on the lines
The lines you see online are approximate. They're good for finding a lot and its parcel number, but a legal boundary question needs the recorded plat or a surveyor.