- ISBNs come from your country's official ISBN agency (Bowker in the US).
- Retailers like KDP offer a free ISBN, but list themselves as publisher.
- Each format (ebook, paperback, hardcover, audio) needs its own ISBN.
- Owning your ISBN lets you list yourself or your imprint as publisher.
- Some countries provide ISBNs free through their national library.
Get an ISBN from your country's official agency — Bowker in the US (paid), while many countries (Canada, UK via Nielsen arrangements, and others) provide them free through a national agency. Alternatively, retailers like Amazon KDP assign a free ISBN, but it records them as the publisher of record. Each format needs its own ISBN. Buying your own lets you publish under your name or imprint and use the book across all platforms.
Chapter i·Why it matters
The ISBN decision quietly shapes how professional and portable your book is. A retailer's free ISBN is convenient but lists that retailer as publisher and is tied to their ecosystem; an ISBN you own lets you appear as the publisher, carry the book across every platform, and present a more professional record. Knowing where ISBNs come from — and that each format needs one — prevents confusion at upload time.
Chapter ii·What to include
- Your country's official ISBN agency.
- Whether your country offers ISBNs free.
- A separate ISBN per format.
- The publisher-of-record implication of a free retailer ISBN.
- A decision on owning vs using a retailer ISBN.
- Bulk purchase if you will publish multiple titles.
Chapter iii·Example
A US author plans ebook, paperback, and audio editions. Rather than take KDP's free ISBN (which would list Amazon as publisher), she buys a small block from Bowker, assigns one per format, and lists her own imprint as publisher. Her book now carries a consistent, professional identity across every store.
Chapter iv·Related questions
WriteLoom's Sell studio tracks an ISBN per format in one place, so your publishing identity stays consistent across stores.
See the Sell studio