While "Quad Remesher Blender Addon UPD Free Download" is a popular search term, it is important to clarify that developed by Exoside . It is widely considered the industry standard for automatic retopology in Blender, but it is not officially free. Official Versions & Pricing

: You can download a 30-day free trial from the Exoside website to test its capabilities before purchasing.

Summary

It is important to be transparent: Quad Remesher is a paid, commercial plugin.