What are KDP's hardcover limits?

KDP's hardcover window is 75 to 550 pages, on five trim sizes: 5.5 × 8.5, 6 × 9, 6.14 × 9.21, 7 × 10 and 8.25 × 11. The window is KDP's manufacturing specification, not a law of bookbinding — other printers case-bind further, Lulu to 800 pages, and they will jacket the book too. A 600-page book has no KDP hardcover; it may still have a hardcover.

What is the difference between case laminate and a dust jacket?

Case laminate prints the cover artwork onto the wrap around the rigid boards — one cover spread, no flaps, nothing to tear, and the only hardcover construction KDP prints. A dust jacket is a loose printed wrapper with fold-over flaps; it needs a printer that offers one, plus decisions KDP never asks for, such as the colour of the case beneath and the foil on the spine. Laminate is the pragmatic default; the jacket is the traditional object, and mostly a different vendor's product.

Does a hardcover need its own ISBN?

The hardcover needs an ISBN different from the paperback's — it is a different edition, with its own price. (The ebook needs no ISBN at all, unless you want one.) Each format is its own product, and Amazon normally links them onto one product page when the metadata matches. The counting rules are in the ISBN guide.

Publishing a hardcover

The hardcover is the trade’s prestige object, and print-on-demand made it cheap to add — which is why so many self-published hardcovers are paperback interiors in a case, and read as one. The format has its own body, its own cover geometry and its own buyer. Done properly it is the most durable and most giftable edition of the book; done casually it is a price tier.

The constructions

A case-bound book is a text block and a rigid case, made separately and then cased in — the block’s endsheets attached to the boards. The block itself may be adhesive-bound or sewn; the case is what makes it a hardcover. What covers the case is the choice, and KDP’s part of that choice is narrow:

Case laminate — KDP’s only construction. The artwork is printed onto the material that wraps the boards. The cover is still one spread — back, spine, front — but its geometry is not the paperback’s scaled up: the wrap folds around the board edges, hinge allowances sit where the cover meets the case, and the safe areas differ. KDP publishes a hardcover-specific cover template and calculator; build from those and from this edition’s own spine arithmetic, never from the paperback’s file. The same wrap discipline applies — only more so.

Dust jacket — another printer’s product. A jacket is a loose printed wrapper around the case, with flaps folding inside the covers, and it is where hardcover tradition lives: the flaps carry the description and the author biography, and the object on the shelf reads as a trade hardcover. KDP does not print jackets. Jacketed hardcovers come from POD printers that offer them — Lulu, for one, pairs a printed jacket with a linen case whose colour and spine foil are chosen separately. The jacket spread is wider — flap, back panel, spine, front panel, flap — with the fold positions coming from the printer’s template rather than drawn onto the artwork. It is the more demanding build, and the traditional object; many handsome gift hardcovers are laminate or cloth without one.

The limits

Print-on-demand hardcovers live inside narrower windows than paperbacks:

75 to 550 pages at KDP — a product specification, not a property of case binding, which goes further elsewhere: Lulu case-binds to 800 pages, jacketed or not. A 600-page book has no KDP hardcover; it may still have a hardcover. A slim novella under 75 pages has no KDP hardcover either, and other printers start lower.
Five trims — 5.5 × 8.5, 6 × 9, 6.14 × 9.21, 7 × 10 and 8.25 × 11 — a shorter list than the paperback’s. The trim decision is revisited, not inherited, and the trade-offs are the ones in choosing a trim size.
A cover built from this edition’s arithmetic. The block’s thickness is driven by page count and paper, as with a paperback; the case adds boards, hinges and wrap around it, which is why the cover template, not a scaled paperback file, defines the geometry.

The page ceiling bites sooner than people expect, and it interacts with design: a large-print or illustrated edition that is already long in paperback has no KDP hardcover at all. The page count estimate tells you which side of the window the book lands on before the edition is designed.

The economics

A hardcover’s unit print cost is a multiple of the paperback’s — KDP’s own 300-page black-and-white example is $9.25 against $4.60, roughly twice, and the gap widens with length and with colour. It prices accordingly: trade hardcovers usually command a materially higher list price than the paperback, and the buyer is paying for the object; a hardcover at a paperback price reads as a mistake.

Per-copy margin can still be strong, because the print cost is high but the price is higher. The edition’s honest business case, though, is rarely raw units:

Gift and keep. Books bought as presents, and books bought by readers who already own the paperback because the series mattered to them, are object purchases — the case, the jacket where there is one, the weight in the hand — and the object is the product.

Libraries. Libraries buy case-bound books and tend to keep them through many circulation cycles, so a durable hardcover is the natural library edition. Two cautions keep the plan honest: acquisition policies differ, and a print-on-demand case is not a purpose-built library binding — that is its own standard, ANSI/NISO Z39.78, with materials and construction a POD case does not promise. Distribution is the other constraint: KDP’s expanded distribution, the route toward bookstores and libraries, is open to paperbacks only, so a hardcover aimed at libraries needs an Ingram-sized distributor behind it — the channel question again.

Signal. A hardcover on the shelf, at a launch, in a shop window, states what the book is. The edition is advertising that can be sold.

What the edition changes

Because the hardcover is a separate product with its own ISBN, price and cover, the practical work is:

Confirm the page count fits the chosen printer’s window, and the trim from that printer’s list.
Choose the construction — laminate everywhere; a jacket only where a printer offers one.
Build the cover from this edition’s template and spine arithmetic; flaps typeset if there is a jacket.
New ISBN, new listing, price at the hardcover tier.
Order the proof in hand before publishing. Case-bound books are not lay-flat bindings, so the proof will not open like a paperback — what it tells you is the feel, the cover alignment and the quality of the case, none of which a file review catches.

The interior itself is usually shared with the paperback — same PDF geometry at the same trim, if the trims match, with the copyright page’s ISBN line updated — which is the one genuinely cheap part of the edition.

A hardcover is the trade’s prestige object, and print-on-demand turned it into a checkbox — which is exactly why the difference between a considered edition and a checkbox shows. The construction, the case, the spine and the price are the edition.

Nueel builds the hardcover as a distinct edition of the same book — its own trim, its own cover geometry from its own spine arithmetic, its own PDF — so the case edition is designed like the product it is, not scaled from the paperback.

Sources

KDP, Hardcover and Create a hardcover cover
KDP, Paperback and hardcover distribution rights
Lulu, Publishing a print book for global distribution and Upload your cover file

Common questions

What are KDP's hardcover limits?: KDP's hardcover window is 75 to 550 pages, on five trim sizes: 5.5 × 8.5, 6 × 9, 6.14 × 9.21, 7 × 10 and 8.25 × 11. The window is KDP's manufacturing specification, not a law of bookbinding — other printers case-bind further, Lulu to 800 pages, and they will jacket the book too. A 600-page book has no KDP hardcover; it may still have a hardcover.
What is the difference between case laminate and a dust jacket?: Case laminate prints the cover artwork onto the wrap around the rigid boards — one cover spread, no flaps, nothing to tear, and the only hardcover construction KDP prints. A dust jacket is a loose printed wrapper with fold-over flaps; it needs a printer that offers one, plus decisions KDP never asks for, such as the colour of the case beneath and the foil on the spine. Laminate is the pragmatic default; the jacket is the traditional object, and mostly a different vendor's product.
Does a hardcover need its own ISBN?: The hardcover needs an ISBN different from the paperback's — it is a different edition, with its own price. (The ebook needs no ISBN at all, unless you want one.) Each format is its own product, and Amazon normally links them onto one product page when the metadata matches. The counting rules are in the ISBN guide.
Who actually buys hardcovers?: Gift buyers and collectors, who buy the object rather than the text, and readers already committed to a series. Libraries buy case-bound books too, and tend to hold them longer, but acquisition policies differ and a print-on-demand case is not a purpose-built library binding, which has its own standard. In the long run a hardcover rarely outsells the paperback; it sells to a different reader and it signals the book's stature on the shelf.