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ISBN Guide
& validator

Find out how many ISBNs your book needs and check whether an ISBN-13 is valid.

Your book
Formats you will publish
Check an ISBN-13optional
ISBN rules vary by country. In the US, ISBNs are issued by Bowker. Each format and edition needs its own number.
ISBNs you need
2
ISBNs, one per format
ISBN check
Valid
Barcode
Print editions
Paperback, hardcover, eBook and audiobook each need a separate ISBN. Registering them in your own name makes you the publisher of record.
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What an ISBN is

An ISBN (International Standard Book Number) is a unique 13-digit identifier for one format of one edition of a book. Retailers, distributors and libraries use it to track and order your book.

Do you need your own ISBN?

Some platforms offer free ISBNs, but they list the platform as publisher and only work on that platform. Owning your ISBNs gives you control and lets you publish the same edition everywhere.

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