books
Project Gutenberg (Gutendex)
The classic collection of around 75,000 free public-domain ebooks, with the Gutendex service exposing its catalogue as JSON for searching by title or author. You can also browse and download directly from the Gutenberg website. It is the go-to for complete, free ebook texts of out-of-copyright works, though the catalogue query can be slow or occasionally time out.
Why it’s useful & how it works
gutenberg.org blocks our direct IP (geo) but works via proxy; Gutendex page is up yet its /books search query TIMED OUT both ways in probe (slow/overloaded). Use Gutendex for lookups but expect slowness — re-probe; fall back to gutenberg.org via proxy + mirror links.
What’s inside
~75k books.
API access
https://gutendex.com/books?search= ... ; https://gutendex.com/books/ <id>
Access
Programmatic API access (a key may be required — see the API tag).