IngramSpark vs KDP: which fits your book?

The shortest honest answer: KDP is Amazon’s own press; IngramSpark is the door to everywhere else. KDP prints books sold on Amazon. IngramSpark feeds the Ingram catalogue, through which bookstores, libraries and most other retailers order. Many authors use both — the same interior, two uploads — and for most trade books that is what we recommend. But the differences matter.

Distribution

KDP’s reach is Amazon, plus an optional “Expanded Distribution” that places your book in other catalogues at a lower royalty — convenient, but bookstores often will not order through it. IngramSpark’s distribution is the industry’s standard wholesale channel: physical stores and libraries can order your book on normal trade terms, which is a precondition for real bookstore presence. If your readers buy on Amazon and nowhere else, KDP alone is enough. If you dream of shelves, you need Ingram.

The ISBN question

KDP will give you a free ISBN — but that ISBN names Amazon as the publisher of record and can only be used on KDP. IngramSpark requires an ISBN you own. Owning your ISBN means you are the publisher everywhere, forever, on every platform. If there is any chance your book will travel beyond Amazon, buy your own ISBN once and use it on both platforms.

Print options and files

IngramSpark offers more: hardcover formats KDP does not match, more paper and trim choices, and stricter file requirements — its cover files in particular must be built to Ingram’s own template, spine width calculated from your exact page count and paper. KDP is more forgiving and its preflight is faster. Neither forgives a wrong spine, and both will reject the same sins: unembedded fonts, low-resolution images, missing bleed.

	Amazon KDP	IngramSpark
Best for	Amazon-first sales	Bookstores, libraries, wide retail
ISBN	Free (Amazon as publisher)	Your own required
Hardcover	Limited range	Broad range
File strictness	Moderate	Strict — template-built covers
Setup	Free	Check IngramSpark’s current terms

Terms and fees change, so check IngramSpark’s current terms before you publish.

Our usual recommendation

Publish on both: KDP for Amazon (where its royalty and speed are best), IngramSpark for everywhere else, one ISBN you own, and files built once to the stricter standard so both platforms accept them. It is the setup we recommend for most trade books — and it costs you nothing in duplicated effort when the files are prepared properly the first time.