Self-publishing · ISBN planning
How many ISBNs do I need?
Every format and edition needs its own number. Count them for your catalogue and see what each route costs.
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ISBNs needed
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How many ISBNs does a book need?
Each format needs its own ISBN: KDP says a paperback and a hardcover each need one, and that eBooks and low-content books are the only formats where an ISBN is optional. Library and Archives Canada states the general rule: each format and edition of a publication must have its own ISBN. So the count is titles x formats x editions.
KDP offers a free ISBN for paperbacks and hardcovers only, and it can only be used on KDP; the imprint shows as "Independently published". If you want to publish the same paperback through other retailers or IngramSpark, you will need your own ISBN. Eligible Canadian publishers, including self-publishing authors physically in Canada, can request free ISBNs from ISBN Canada.
Worked example. Two titles, each as paperback, hardcover and eBook, one edition: 2 x 3 = 6 ISBNs. Using KDP free ISBNs covers the 4 print ISBNs; the 2 eBooks need none on KDP.
Frequently asked questions
Do I need a separate ISBN for paperback and hardcover?
Yes. KDP states that each format of your book, such as paperback versus hardcover, needs its own ISBN.
Does a KDP eBook need an ISBN?
No. KDP says eBooks and low-content books are the only formats where an ISBN is optional.
Can I use a free KDP ISBN elsewhere?
No. Free ISBNs from KDP can only be used on KDP, and the imprint appears as "Independently published".
Are ISBNs free in Canada?
Eligible Canadian publishers may request free ISBNs from Library and Archives Canada, including self-publishing authors physically located in Canada. French-language-only publishers apply through BAnQ.
Does a new edition need a new ISBN?
Library and Archives Canada says each format and edition of a publication must have its own ISBN. For borderline cases such as a colour versus black and white version, it advises contacting Library and Archives Canada.
Sources
Checked
KDP supports the per-format rule, the free-ISBN scope and the optional eBook ISBN. Library and Archives Canada supports the free-ISBN eligibility and the per-edition rule. ISBN prices are your own input because agencies set and change them. Runs entirely in your browser. Nothing you type is sent or stored.
Scope
Planning aid based on the pages cited, checked on 15 October 2026. Rules differ by country and ISBN agency; confirm with yours.