KDP cover size calculator
The full cover is one artboard: back cover, spine and front cover side by side, plus bleed on every outer edge. Enter your book and the numbers below are the ones to set up your document with.
Showing a paperback, 6" x 9", 120 pages, white paper.
- Spine width
- 0.270 in120 pages x 0.002252 in per page
- Full cover width
- 12.520 inBack cover + spine + front cover, with bleed
- Full cover height
- 9.250 inTrim height with bleed
- Bleed
- 0.125 inOn every outer edge
- Safety margin
- 0.375 inKeep text and logos inside this
- Barcode zone
- 2 x 1.2 inBottom right of the back cover; leave it clear
How the spine width is worked out
Spine width is page count multiplied by the caliper of one sheet, and the caliper depends on the paper: white is 0.002252 in, cream 0.0025 in, colour 0.002347 in. Changing paper changes the spine, which changes the whole artboard — which is why a cover drawn before the interior was finished usually has to be redrawn.
Why a hardcover is wider than its trim
A hardcover case wraps around the boards, so KDP asks for an extra 0.5 in on every outer edge on top of the 0.125 in bleed. Switch the binding above to see the artboard change.
Open this in the workspace to see the artboard drawn, save it against a book, and export a spec sheet.
The rules behind these numbers
- Paper choice changes your cover
Spine width depends on paper stock, so switching paper after designing a cover invalidates it.
- Text on the spine
KDP will not print text on a spine below 79 pages, and what you do print has to fit between the two folds.
- Bleed and where it applies
Bleed adds 0.125" beyond the trim so ink runs off the cut edge, and applies to outer edges only.
- Cover text sits too close to the trim
Live content on a cover must stay 0.375" inside the trim edge — a different, larger figure than an interior's outside margin.
- Artwork sits under the barcode
KDP prints a barcode in a 2" x 1.2" area at the bottom right of the back cover. Anything there will be covered.