How to check if an object is partially outside of the camera view?

I have a scene that loads an asset from the web and you have a camera that orbits this object allowing you to zoom in, out, rotate..etc something like a 3D model viewer. I want the camera position to adjust depending on the object's size so that when the object is loaded not a single part of it is outside the camera view.

I have tried with raycasting and world to viewport point but none of these approaches work as I want. How can I make sure that the camera's position is far enough so that I can see the complete object?