KDP cover & spine width calculator
Pass KDP’s review on the first try.
Spine width, full-cover dimensions, and safe-zone diagrams — instant, in-browser, and verified against KDP’s official template.
Multipliers verified against KDP’s official template generator
- Full cover
- 12.7004 × 9.2500 in
- Other unit
- 322.59 × 234.95 mm
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});</script>Verified math
Every multiplier and bleed value is golden-tested against KDP's official cover-template generator on every commit.
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All math runs in your browser. No account, no upload, no cookies set by the calculator itself.
Standards-grade output
Downloadable SVG templates open cleanly in Affinity Publisher, Illustrator, Inkscape, and Figma at the exact KDP-spec geometry.
KDP spine multiplier reference
Multiply your interior page count by the multiplier for your format and paper. Every value is verified against KDP’s official cover-template generator.
| Format | Paper | Multiplier (in/page) |
|---|---|---|
| Paperback | White (B&W interior) | 0.002252 |
| Paperback | Cream (B&W interior) | 0.0025 |
| Paperback | Standard Color | 0.002252 |
| Paperback | Premium Color | 0.002347 |
| Hardcover (Case Laminate) | Any | 0.002347 |
Frequently asked
- What is the KDP white-paper paperback spine width formula?
- The KDP white-paper paperback spine width formula is 0.002252 inches per page. Multiply your interior page count by 0.002252 to get the spine width in inches.
- What is the spine multiplier for cream paperback?
- 0.0025 inches per page. Cream pages are slightly thicker than white, so a 300-page cream paperback has a 0.75″ spine versus 0.6756″ for white.
- Does KDP hardcover use a different multiplier than paperback?
- Yes. Case-laminate hardcover always uses 0.002347 inches per page regardless of paper choice, and adds 0.4″ hinge each side of the spine plus 0.51″ wrap on the outside edges.
- What's the difference between paperback and hardcover bleed?
- Paperback bleed is 0.125″ on every outside edge. Hardcover does not use traditional bleed; instead it has a 0.51″ wrap that folds inside the case.
- What is the minimum page count for spine text on a KDP cover?
- 79 pages. Below 79 pages, the spine is too narrow for KDP's automated review to accept printed text or graphics.
- What is the KDP barcode size and placement?
- The recommended barcode area is 2″ × 1.2″ in the bottom-right of the back cover, with at least 0.25″ clearance from the spine and trim edges and 0.76″ from the bottom. The minimum acceptable size is 1.4″ × 0.8″.
- What page-count range does KDP allow?
- KDP paperback supports 24–828 pages. Case-laminate hardcover supports 75–550 pages. Maximums are also subject to trim-size-specific limits.
- What file format does KDP require for cover upload?
- A single flattened PDF combining back cover, spine, and front cover, with fonts embedded, no crop marks, 300 DPI minimum, CMYK preferred. Files should be 40 MB or less; 650 MB is the hard limit.