That’s what I listed a bunch of other book databases
Unfortunately, I don’t think there’s an equivalent of TMDB for books. The main issue is especially international coverage. You can probably find decent open data for books in a single language but I haven’t found a good database that covers multiple languages well.
I read books in four languages (English, French, German and Japanese) and tried many book tracking services over the years and couldn’t find one that had good coverage in all languages I need.
That’s not the case for Trakt/TMDB. While its coverage of non-English media is noticeably worse, it still has decent coverage, even for obscure non-English titles. Trakt is really creating a great UX on top of the TMDB data but they’re not in a capacity to start a database of this size and complexity on their own.
E.g. I just did a search of a Japanese book off the top of my head and only WorldCat found it, Open Library, GoogleBooks and ISBNdb all found nothing.
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