Where are my iBooks stored in macOS?

I am looking here for my iBooks in macOS:

/Users/'USERNAME'/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks

But the folder is empty. When I open iBooks (the App) in Sierra, then all my books are there.

So what is happening here? Is Apple just hiding my books now? Where can I display/find them?

If you’ve enabled iCloud, they’re stored in Mobile Documents folder.

Here’s the full path to books you've added:

~/Library/Mobile Documents/iCloud~com~apple~iBooks/Documents/

Here's the full path to books purchased through the iBooks store:

~/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks

The path is only accessible via Terminal. Going through Finder will only redirect you to the iCloud folder. So open up Terminal:

For books you've added type in:

open ~/Library/Mobile\ Documents/iCloud\~com\~apple\~iBooks/Documents

For books you've bought on the iBooks store type in:

open ~/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks

This will open a Finder window with your iBooks in it.

I simply dragged the books onto a folder of my choice in Finder and got the epub files that way.

/Users/USERNAME/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks

This worked for me in Sierra.

If you've enabled iCloud for iBooks [1], any books you've uploaded are stored in:

~/Library/Mobile Documents/iCloud~com~apple~iBooks/Documents/

Although you can't see it when you browse iCloud Drive in the Finder, the are two easy ways to get to it:

• Open any PDF; when it opens in Preview, right-click the titlebar and click "iBooks (iCloud)".

  or

• In the Finder, press ⌘ command⇧ shiftG and paste the path.

Note that books you've purchased from the iBooks Store are stored in a different location:

~/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks

You can open this folder the same way (⌘⇧G), but there's not much you can do here. If you want to add books to your library, add them to the iCloud folder, not here.

Just checked and confirmed locations are still accurate in macOS High Sierra (10.13.4).

[1] If you're not sure if iCloud for iBooks is enabled (understandable, since you only see it the first time you open iBooks, and there's no setting within the app), go to System Preferences → iCloud, then click "Options" next to iCloud Drive. Look for iBooks in the list. If it's checked, you're using iCloud for iBooks.

In Sierra, I found some of my iBooks at the location listed above:

/Users/'USERNAME'/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks

However, they were not all there, only a small handful. When I went to iBooks and downloaded them from the cloud, then they started to show up as ePub files there.