Reducing poly counts on CAD files
Overview
If you want to use a 3D CAD file to create a virtual item for Breakroom (for instance, if you have a CAD file of your corporate headquarters), you may need to reduce the polygon count to achieve optimal performance in a runtime environment. You can consult our Review Policies for more information about recommended poly counts.
Reducing poly counts in Blender
You can use the Decimate modifier in Blender to lower the polygon count of your model. Start by importing your model into Blender. Select the model in the Hierarchy.

Pictured: Blender, with a high-poly model imported for use and selected.
With the model selected, click the wrench icon in the bottom right panel. Click on the Add Modifier drop-down menu, and select Decimate.

Pictured: The location of the wrench icon and the Add Modifier menu.
In the Decimate panel, you can see that the face count for this object is currently 1,007,616. Adjust the Ratio slider to reduce the face count, and then click the Apply button.

Pictured: The Decimate panel, with the ratio slider and Apply button visible.
In the picture above, you can see that the ratio has been reduced to 0.8, which is 80% of the original. This gives us an adjusted face count of 806,092.
More information on using the Decimate modifier can be found in Blender's own documentation.
Recommended software
In addition to Blender, there are a number of software solutions for reducing polygon count on large files. We recommend the following: