Definition
ISBN
An ISBN is the 13-digit International Standard Book Number identifying one edition of one book in one format. A paperback, a hardback and an ebook each need their own.
The identifier is tied to the format and the publisher of record, which is the practical consequence authors miss: a free ISBN supplied by a retailer lists that retailer as publisher and cannot be carried to another platform, while a bought one is yours across every channel. Prices vary enormously by country because national agencies set them — free in some, expensive singly and cheap in blocks in others. A new edition with substantially changed content needs a new number; a corrected reprint does not.
Related tools & guides
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