It is part of Fredo6’s “FredoTools” suite but is also distributed as a standalone extension.
Before we dive into downloads, let’s understand why this tool is legendary. Round Corner Extension Sketchup Free Download
If you tell me your (e.g., Make 2017, Pro 2023) or the specific object you are modeling, I can suggest the best settings for your geometry. It is part of Fredo6’s “FredoTools” suite but