LibraryThing APIs

thingISBN takes an ISBN and returns a list of ISBNs from the same "work" (ie., other editions and translations). Uses the same format as OCLC's xISBN. To use thingISBN, point your browser at a URL like this, replacing the ISBN as appropriate: Examples and more details here.
thingTitle takes a title and returns a list ISBNs from the most likely LibraryThing "work," the LibraryThing title and a link to the LibraryThing work page. Examples and more details here.
thingLang takes an ISBN and returns the language of the book, using language codes from MARC records, and from the Group Identifiers embedded at the start of the ISBN format. Results are in the form of a three letter MARC language code. Examples and more details here.

Easy Linking

ISBN. You can link to a work page on LibraryThing just by throwing the ISBN into the URL. Examples:

Sloppy title. You can also link to a book's work page by putting the book's title in the URL. Spaces can be represented by underscores, + signs, or even simply as spaces (more here). Examples:

Data Feeds

We have a number of very large periodic data feeds available:

  • AllLibraryThingISBNs.xml.gz. A simple list of all ISBNs in LibraryThing.
  • WikipediaCitations.xml.gz. A list of ISBNs to Wikipedia articles (described on the blog).

Terms of Use

  • By using any of LibraryThing's APIs you agree to these terms of use.
  • thingISBN, thingTitle and AllLibraryThingISBNs.xml.gz are available for non-commercial use only (commercial use requires our written permission).
  • thingLang and WikipediaCitations.xml.gz are released for both non-commerical and commercial use, but the rest of these rules still apply.
  • You can make only one request per second on an API (if you're going to hit it more than 1,000 times/day, you must notify LibraryThing - we'd love to hear what you're doing).
  • APIs are provided "as is," without any promises or guarantees of any sort. You're on your own!
  • We reserve the right to change these terms and generally make things up as we go along.

What do you want?

If you'd like something we don't already have up here, or if you have any questions about the available APIs, email Tim at timAT