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What are ISBN's?

International Standard Book Numbers (ISBN)

What Are They...and, Why Are They So Important?

Since 2007, the ISBN has been a 13-digit number that uniquely identifies books and book-like products published internationally. Previously, the ISBN was a ten-digit number. 

What is the purpose of an ISBN? 

The purpose of the ISBN is to establish and identify one title or edition of a title from one specific publisher and is unique to that edition, allowing for more efficient marketing of products by booksellers, libraries, universities, wholesalers and distributors.

What are the unique characteristics of an ISBN? 

Each format or binding must have a separate ISBN. Once assigned, an ISBN can never be reused. An ISBN is printed on the lower portion of the back cover of a book above the bar code and on the copyright page.

Examples of formats which require a unique ISBN include: 

Hardcover versions of textbooks 

Paperbound versions of textbooks 

Indiana Editions of textbooks 

National Editions of textbooks 

Teachers Editions of textbooks 

Examination copies of textbooks (often shared with districts during district new adoption process) 

Revised editions of textbooks 

E-book format of textbooks that are purchased from publisher 


Some ISBN's end in an "X," in which case enter the "X" into the search string

Does the ISBN-13 have any meaning imbedded in the numbers?

The five parts of an ISBN are as follows:

1. The current ISBN-13 will be prefixed by "978"...usually

2. Group or country identifier which identifies a national or geographic grouping of publishers

3. Publisher identifier which identifies a particular publisher within a group

4. Title identifier which identifies a particular title or edition of a title

5. Check digit is the single digit at the end of the ISBN which validates the ISBN