ISBN Lookup

What is an ISBN?

ISBN stands for International Standard Book Number. It's a unique numeric commercial book identifier that's assigned to each edition and variation of a book. The ISBN is 13 digits long (10 digits for books published before 2007).

What's the difference between ISBN-10 and ISBN-13?

ISBN-10 was the standard format until 2007, consisting of 10 digits. ISBN-13 is the current standard, beginning with the prefix 978 or 979. All ISBN-10s can be converted to ISBN-13s, but not all ISBN-13s can be converted back to ISBN-10s.

Where can I find a book's ISBN?

The ISBN is typically printed on the back cover of a book above the barcode. It can also be found on the copyright page (usually one of the first few pages of the book), often near the publisher information.

Why isn't my book showing up in the search?

There are several possible reasons:

• The book might be very new or not yet published
• The book might be self-published or from a small publisher not in our database
• The ISBN might be entered incorrectly
• The book might be very old (published before ISBNs were widely used)

Can I search by title or author instead of ISBN?

Currently, ISBNLookup only supports searching by ISBN. This ensures precise results for the exact edition you're looking for. For title or author searches, we recommend using services like Google Books or Goodreads.