| KDP | IngramSpark | |
|---|---|---|
| What it is | Amazon's own print-on-demand + storefront | Ingram's POD + wholesale distribution network |
| Where books sell | Amazon marketplaces; optional Expanded Distribution to other channels at a lower royalty | ~40,000 retailers & libraries: Barnes & Noble, indie bookstores, libraries, schools |
| Upload cost | Free; revisions free | Free; and since February 2026, revision uploads are free too — older guides still warning about Ingram revision fees are out of date |
| ISBN | Free ISBN available (Amazon imprint, KDP only) | Your own ISBN required — no free option |
| Royalty model (Amazon sales) | 60% of list minus print cost (50% under $9.99) | List minus wholesale discount (you set it, typically 40–55%) minus print cost |
| Formats | Paperback + case-laminate hardcover | Paperback, case laminate, cloth/dust-jacket hardcovers, more trim sizes |
| File personality | Forgiving in places (no blank-page rule) | Stricter: blank final page, 0.5″ margins, PPI spine math, embedded-font enforcement |
The ISBN rule decides the order of operations
If you take KDP's free ISBN, that edition lives on KDP forever and can never move. If you buy your own ISBN, the same paperback ISBN can be published on both platforms (identical specs), which is the standard dual setup: KDP serves Amazon (fast, best royalty there), IngramSpark serves bookstores and libraries — and you do not enroll that ISBN in KDP's Expanded Distribution, or the two channels fight over the same book. Full detail in ISBN & barcode rules.
The file differences that matter
- Spine math differs. KDP: pages × paper factor (white 0.002252″, cream 0.0025″). Ingram: pages ÷ PPI (white 444, cream 400). Close, not identical — a KDP cover is measurably wrong on Ingram at high page counts. The spine calculator shows both.
- Margins: KDP's gutter table starts at 0.375″; Ingram floors everything at 0.5″. Build to Ingram's floor and you satisfy both.
- Final page: Ingram requires it blank; KDP doesn't care. A blank final page costs nothing on KDP — build it in once, use the file everywhere. See the blank-page rule.
- Barcode zones differ slightly (KDP 2″ × 1.2″; Ingram 1.75″ × 1″, both bottom-right, both placed by the platform).
- Cover bleed: Ingram covers always carry 0.125″ bleed on all sides; KDP covers too — it's KDP interiors that are often no-bleed.
Have files that passed one platform and failed the other? That's our home turf. Send us your interior and cover PDFs and we'll run both checklists — 6 KDP checks, 7 IngramSpark checks — and tell you in plain English what doesn't transfer. The check is free. Get the free check →
Which one first?
Start on KDP if: your buyers are on Amazon, your budget is zero, you're testing a book's viability. Free uploads, free revisions, fastest feedback loop in publishing.
Add IngramSpark when: bookstores, libraries, or schools are realistic buyers; you want hardcover with a dust jacket; you're publishing children's books (libraries buy them in quantity); or a KDP proof showed you the book deserves a wider life.
Ingram first is rare but real: books aimed at institutions from day one, or formats KDP doesn't make.
The honest limit
Distribution is not sales. IngramSpark makes your book orderable by 40,000 stores; it does not make 40,000 stores order it — bookstore sales still come from demand, reviews, and your own pushing, and most Ingram titles sell most of their copies through online retailers anyway. Likewise KDP's Expanded Distribution is not a substitute for Ingram: lower royalty, patchier availability. Use each platform for the job it's actually built for — and since revisions are now free on both, the real cost of a bad file is no longer fees; it's the weeks a rejected book isn't selling while you fix it.
Or send us the files — the check is free
Email your interior and cover PDFs and we'll tell you exactly what's wrong — in plain English, free, within 48 hours. If it does need fixing, the by-hand fix is $19 and we redo it free if the platform rejects it for a formatting issue we were hired to fix. We rebuild files to be compliant with the platform's published spec — that's the promise we can keep.