Reply To: Converting existing .indd to .indb file

Glad you could come to the event, Aldo!
You cannot convert a document into a book. The book contains multiple InDesign documents. So you would have to break the big document into smaller documents first, and then add them.

HOWEVER, I would ask: Do you really need to convert it into a book? I always try to keep InDesign publications in a single document if I can. Once the file gets over 400 pages, then maybe it is better split up. But not necessarily. You can make InDesign files with over 1000 pages and they can be okay.