March 03, 2016 / by Open Data Portal Team / In Open Data , Data Portal

What coordinate system do our shapefiles use?

We frequently get questions about what coordinate system our shapefile datasets use.  The answer is State Plane Illinois East NAD 1983.

It is important to note that this answer applies to the files we upload – those of view type Files and Documents and “Original” exports of our newer map format.  The “Shapefile” exports are created by the Data Portal software, even if the original file was also a shapefile, and use WGS84.