The Internet Archive's Open Library is an open repository of millions of books and book information. The Open Library REST API Track this API allows developers to interact with book records, cover images, subject listings, user lists, search-inside and more.What can you do with a free API?
With the help of a free API, you can do testing and create flexible, powerful apps in record time. With a quick Google search, you’ll discover tens of thousands of free and open APIs — all well-made and easily accessible to developers all over the world.What's the ISBN API for open library books?
The ISBN API is a special case and alternative approach to arriving at an Editions page. Instead of "/books", a path of "/isbn" is used, followed by a valid ISBN 10 or 13.