What size should a KDP paperback cover be?

The full wrap is (2 × trim width) + spine width + 0.25" of bleed wide, and trim height + 0.25" of bleed tall. For a 6×9 book with 300 cream pages that is 13.0 × 9.25 inches — 3900 × 2775 pixels at 300 DPI.

How do I calculate my book's spine width?

Multiply your page count by the paper caliper: 0.0025" per page for cream, 0.002252" for white, 0.002347" for premium color. Lulu uses pages ÷ 444 plus a fixed 0.06" cover-board allowance for every paper.

What size should a Kindle ebook cover be?

Amazon recommends 1600 × 2560 pixels (a 1:1.6 ratio) in JPEG or TIFF, under 50 MB.

Book cover size calculator — KDP & Lulu paperback dimensions

Book cover size calculator

Full-wrap and ebook dimensions for supported Amazon KDP and Lulu perfect-bound paperbacks, drawn to scale. IngramSpark and Barnes & Noble Press require their official cover templates.

COVER SIZE COMPUTER

Printer

Trim size

Page count

pages

Paper

Amazon KDP spine = pages × paper caliper (cream 0.0025″ · white 0.002252″ · premium color 0.002347″). Lulu perfect bound uses pages ÷ 444 + 0.06″. Bleed is 0.125″ on every outside edge. IngramSpark and B&N are not calculated because their official templates depend on product and stock choices this tool does not collect. Always confirm the final file against the printer's template.

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One-click covers, print-ready

Front, spine and back — a full wrap-around cover sized exactly for KDP, plus a matching Kindle edition. All the design tools you need for instant, print-ready art. Free preview, no card.

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How the numbers are computed

A paperback cover is printed as one sheet: back cover + spine + front cover, plus 0.125″ of bleed on the outside edges. So the full canvas is:

width = (2 × trim width) + spine + (2 × bleed)
height = trim height + (2 × bleed)

On KDP the spine grows with every page: cream is 0.0025″ per page, white 0.002252″, and premium color 0.002347″. That's why you can't reuse one cover file across editions with different page counts — a 20-page difference moves the spine by a visible margin.

Ebook covers are simpler: KDP recommends 1600 × 2560 pixels (a 1:1.6 ratio) for Kindle.

Want the file made for you at exactly these dimensions? The free cover studio paints the art, wraps it around the spine, and exports the press-ready PDF with this math baked in.