Changing Sharepoint to modern experience and back

Question

The entire sharepoint is set in classic experience, recently I have been creating document libraries that are in modern experience.

How to change the entire SharePoint form classic to modern experience ?

The other thing that concerns me is that in case I want to change back to classic experience because of different reasons.

Can I switch back to classic experience on my entire sharepoint ?

I’m not sure but I think that I heard that once you switch to modern experience this process is irreversible.

Answer 1

You can control classic and modern experience of SharePoint of list and libraries in its respective settings.

Go to List/Library Settings -> Advanced settings, you will find below options. By default if you choose default experience, list and library experience will be inherited from site(be it classic or modern) and if you want to control as list/library level, you can choose any of other 2 options.

For pages which are created using classic experience, needs to be converted to modern(refer this link), but if page is created in modern experience, you cannot convert, you have to recreate page.

Answer 2

There is a site collection feature "SharePoint Lists and Libraries experience". You could activate this feature to turn off the new SharePoint list and library experience for this site collection.