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Open Library API

Book, author and ISBN data plus cover images for 20M+ titles, no key

Open Library (an Internet Archive project) offers free, keyless web APIs over a catalog of 20M+ books. You can search by title, author or ISBN, fetch work and edition records, and pull cover images by ISBN or Open Library ID. It also has a covers endpoint and bulk data dumps.

Free tier

Free, no key (low-volume; non-profit, asks you to cache and be considerate)

Rate limits

Not published; non-profit service requests caching, a descriptive User-Agent and no hammering. Bulk needs use monthly data dumps

Auth

No key

Base URL

https://openlibrary.org

What you'd build with it

  • Enrich an ISBN lookup with title, author and cover image
  • Build a book-search feature or reading-list app
  • Resolve a book title to subjects and descriptions for a recommender
  • Fetch cover art via covers.openlibrary.org by ISBN

Key endpoints

  • GET/search.json?q={q}Search books and authors, with field filtering
  • GET/isbn/{isbn}.jsonEdition record for a given ISBN
  • GET/works/{id}.jsonWork-level record (title, subjects, description)
  • GET/api/books?bibkeys=ISBN:{isbn}&format=json&jscmd=dataRich book data by bibliographic key
Members

Members get the runnable recipe

Sign in free to copy the example request, see a sample response, and read the gotchas.

Tags

knowledgebooksisbnreferencelibrary