Your paperback artwork does not become a hardcover by being resized. Confirm the hardcover you are actually making, see the case it works out to, and find out exactly what has to change about the artwork before it can go on one.
Read in your browser. Nothing is uploaded, stored or sent anywhere — not the file, not its name, not its size.
Nothing here is filled in for you, and nothing is carried over from a paperback. Each fact is your own confirmation.
Nothing is guessed and nothing is defaulted, so the map stays empty until every fact below comes from you. Once it does, the case is drawn at the exact size your trim, print option and page count work out to.
Preserve, Fill and Custom become available once there is a front raster and a confirmed hardcover destination to place it against. Preserve is the starting point: it keeps every pixel of the file you brought.
Not created here, and deliberately left blank on the map. This tool proves the case geometry and places the front artwork you already have. The back copy, the spine type and the wrap composition are still yours to make — nothing is mirrored, generated or copied across from the front.
A paperback cover is the page block plus a fold. A case-laminate hardcover is a different physical object: two rigid boards a little larger than the pages they cover, a spine sized for the block plus the case itself, a groove beside each side of the spine that the cover folds on, and a band around all four edges that wraps to the inside. None of that exists on a paperback, and none of it can be derived from a paperback measurement.
So the hardcover geometry on this page is calculated by its own engine, from its own transcription of Amazon’s published KDP hardcover pages. It cannot call the paperback calculator, cannot read a paperback spine formula and cannot inherit a paperback trim list — the separation is enforced by the test suite, because the failure it prevents is a confident number that is wrong by the thickness of two boards.
The same separation runs through what you type. A paperback’s trim, paper and page count are facts about a different book; this page will not carry them over, guess them, or default them. It also asks you to state that your page count is the one from the finished formatted manuscript, because the spine is calculated from that number and a planning estimate produces a spine wrong by exactly the difference.
What this page proves is what it can measure: the case dimensions, where every panel and safe area sits, where your artwork lands inside the front panel, how much of it is cropped, and whether the placed artwork still meets Amazon’s 300 PPI cover requirement. What it cannot measure it says it cannot measure, rather than passing it. Amazon retains final review.
It depends on the trim, the page count and the print option, and it is bigger than the paperback cover for the same book. The case adds a board margin on all four sides of the page block, a wrap band that folds to the inside, and a spine sized for the block plus the case construction — so a 6 × 9 hardcover cover is not a 6 × 9 paperback cover with a wider spine. Confirm the three destination facts above and the exact full case size, spine width and every panel rectangle are drawn to scale, with the 300 PPI pixel size beside them.
Not the finished wrap, no — the panels are in different places and the case has boards, hinges and a wrap band the paperback does not. The front ARTWORK is usually reusable, and that is what this page is for: it places your front artwork against the hardcover front panel and shows you the two things that decide whether it survives — whether the shapes match, and whether it still has the resolution to print at the larger size.
Amazon publishes one from its own cover calculator, and that remains the file to lay a cover out on. This page answers the question a blank template cannot: whether the artwork you already have fits the case, and what changes if it does not. It draws the same rectangles — boards, spine, hinges, wrap, safe areas and the barcode reserve — with your artwork placed in them, so you can see the answer before you open a design tool.
Because a case spine is not just the page block. It is the block at the hardcover paper’s own caliper plus a fixed allowance for the case itself, so it comes out wider than the paperback spine for the same book and the same paper. That is also why nothing here reuses the paperback spine formula: it would produce a confident number that is wrong.
No, and the case map says so rather than filling them in. This is front-artwork adaptation: it proves the case geometry and places the front cover you already have. Nothing is mirrored across from the front, no background is generated and no title or author name is set. The back composition and the spine are still yours to make, on the geometry this page gives you.
The count from the finished, formatted hardcover manuscript — the one your interior PDF actually has. Not a word-count estimate, and not the paperback’s count if the hardcover is laid out differently. The spine is calculated from this number, so an estimate produces a spine wrong by exactly the difference. If you enter an odd count, KDP prints on both sides of a sheet and the geometry uses the next even number; the page tells you when that happened and leaves your own number alone.
No, and not reading it is the honest answer rather than a limitation to work around. A flattened wrap is one flat picture: it does not declare where the front panel begins, how wide the spine was, or whether anything important crosses a fold, and those boundaries cannot be recovered from pixels with enough confidence to print a book on. Nothing here will detect panels, guess the spine or stretch a paperback wrap onto a hardcover case. Use the original front artwork, or export the front panel on its own from your design file.
No. The file is read by your own browser to measure it and draw it on the case map, and it never leaves your machine — there is no upload step, no account and no server that sees it. The file name is shown to you so you know which file you picked, and it is not recorded anywhere, including in analytics.
No. Confirming means you accept a specific change to your own artwork — an extension, a crop or a repositioning — and nothing more. The three quality results are reported separately and keep saying what they say: a placement can be fully confirmed while the resolution is still a warning and the safe area is still unverified. Nothing on this page says a cover is KDP-ready, because nothing on this page can know that.