I'm using calibre to convert my books from pdf to mobi. My issue is that I have hundreds of books that are already in the mobi format and I'm looking only to convert the books that aren't already in the mobi format.
When I try to convert all of my books it converts the pdf books into mobi even if they are already in mobi. To convert my book collection is going to take many hours, and I'm wondering if there is a way to mass convert books that aren't already in the output format.
Thank you. Will accept any work around that accomplishes this.