To get the legitimate free version, follow these steps via the SideFX official website :
The primary way to use is through the official Houdini Apprentice license. This version includes virtually all features of the full Houdini FX suite but is restricted to non-commercial use. How to Download and Install SideFX Houdini FX 2020 for Mac Free Download
: Open the launcher, log in, and select "Install Houdini." You can choose the latest production build (recommended for stability). To get the legitimate free version, follow these