Why hardcover is a different size
A KDP hardcover uses a case laminate cover: your artwork is printed on a sheet that wraps around rigid front and back boards and folds over to the inside. Because of that fold and the boards, the printable case is larger than the finished trim size and includes a couple of features paperbacks don't have.
| Element | Approx. allowance | Why it exists |
|---|---|---|
| Wrap | ~0.59″ each outer edge | Folds over and glues to the inside of the boards |
| Hinge gap | ~0.375″ each side of spine | Where the cover flexes as the book opens |
| Board overhang | ~0.125″ | Boards extend slightly beyond the pages |
Indicative allowances to show why the case is larger — always size from a current hardcover template for your trim.
Hardcover spine is calculated differently
Hardcover spine width still grows with page count, but it uses a different factor and a larger base allowance than paperback because of the boards. Set your spine width calculator to hardcover to get the right value, then fold it into the full case width with the cover size calculator.
Don't reuse paperback dimensions
A paperback wrap will not fit a hardcover of the same trim — the wrap, hinge and spine allowances are all different. Size the hardcover case on its own.Designing the hardcover case
- Extend background art through the full wrap so the folded edges are printed.
- Keep titles and text inside the safe zone, away from the hinge and wrap.
- Keep the lower-right back cover clear for the barcode.
- Design at 300 DPI and export a single print-ready case file.
Official hardcover template
Generate a sized hardcover template from the KDP cover template generator and confirm current hardcover trim sizes in the KDP Help Center.Related guides
- Compare with the paperback cover template.
- Troubleshoot with why KDP rejected my cover.
- Lock dimensions first with KDP trim sizes.
How KDPBuilder helps
KDPBuilder helps you prepare a hardcover case sized for the wrap, hinge and hardcover spine that match your trim and page count — with background art carried through the wrap and the barcode corner kept clear. The aim is an upload-ready case file that fits Amazon KDP's hardcover specification.