What are some alternatives?
When comparing Onshape and FreeCAD, you can also consider the following products
SketchUp - 3D for Everyone
Autodesk Fusion 360 - Integrated CAD, CAM, and CAE featuring collaborative editing and cloud-based computation.
LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
SolidWorks - Dassault Systèmes SolidWorks Corp. develops and markets 3D CAD design software, analysis software, and product data management software. SolidWorks is the leading supplier of 3D CAD product design engineering software.
DraftSight - Discover Dassault Systèmes®' DRAFTSIGHT™ Professional CAD software that lets you create, edit, view and markup any kind of 2D drawing. Learn more here.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.