KDP cover size for a 421-page 5×8 premium paperback
Enter your details below and this free KDP cover calculator returns the exact spine width, full-cover dimensions, and a safe-zone diagram for a 421-page 5 × 8 in premium paperback — then download a print-ready template. At 5 × 8 in this is the compact trade size most novels, memoirs, and pocket nonfiction ship in. Premium-color interiors use the thickest 0.002347 in/page stock, so the spine runs wider than a B&W book of the same length. Adjust any field to recompute live, or use it as a paperback spine-width calculator for any page count.
- Full cover
- 11.2381 × 8.2500 in
- Other unit
- 285.45 × 209.55 mm
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Same format, paper, and trim — different page count. Each link is its own pre-computed page.