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KDP Cover Calculator


Checked for accuracy · 30 September 2026

Every number here was read from Amazon KDP's own pages on 30 September 2026: Create a Paperback Cover (formula, 0.125 in bleed, the four paper multipliers, the 79-page spine-text rule, the 0.125 in and 0.0625 in text margins, 300 DPI), Barcodes (2 × 1.2 in, at least 0.25 in from the spine and trim) and Create a Hardcover Cover (0.51 in wrap, 0.4 in hinge, 0.635 in text margin). Page-count limits per trim and paper come from KDP's Set Trim Size page, read 22 September 2026.

The full cover size, spine, safe zones and barcode space for any KDP paperback, plus a template you can download.

KDP’s own cover template is a zip file you have to unpack and read. This does the same sums in your browser using Amazon’s published figures, shows the cover to scale, and hands you a template at print resolution. Change a field and everything updates.

Your cover, to scalebleed safe text area barcode
Scale drawing of the full paperback cover: back, spine and front, with bleed, safe text area and barcode space

Put the template on its own layer under your artwork, and hide or delete it before you export your PDF. KDP will print anything left on the page.

Rather not build the cover yourself?

Our full print wrap is £199, built to the exact page count of your finished interior so the spine cannot drift. Already have artwork? We fit it to KDP's template for £39.

See cover design

How KDP works out the cover size

Amazon publishes the formula on its Create a Paperback Cover page:

Cover width = bleed + back cover + spine + front cover + bleed. Cover height = bleed + trim height + bleed.

Bleed is 0.125 in (3.2 mm) on the top, bottom and outside edges. The spine is the only part that changes with your book, and it depends on two things: the page count and the paper.

Ink and paperSpine per page300-page spine
Black ink, white paper0.002252 in (0.0572 mm)0.676 in (17.2 mm)
Black ink, cream paper0.0025 in (0.0635 mm)0.750 in (19.1 mm)
Standard colour0.002252 in (0.0572 mm)0.676 in (17.2 mm)
Premium colour0.002347 in (0.0596 mm)0.704 in (17.9 mm)

Worked example. A 6 × 9 in novel with 300 pages on cream paper: spine 300 × 0.0025 = 0.75 in. Width 0.125 + 6 + 0.75 + 6 + 0.125 = 13 in. Height 0.125 + 9 + 0.125 = 9.25 in. At 300 DPI that is 3,900 × 2,775 pixels.

The five measurements that get covers rejected

  1. Wrong page count. The spine is built from the page count of the final interior. Add a dedication page after the cover is done and the spine is wrong. Finish the interior, then build the cover.
  2. Text in the bleed. Anything within 0.125 in (3.2 mm) of the trim can be cut off. KDP wants front and back text at least that far inside the trim. The green dashed box on the template is the safe area.
  3. Spine text on a thin book. In KDP’s words: “We only print spine text on books with more than 79 pages.” Under 80 pages, the spine gets colour only.
  4. Spine text too close to the fold. KDP asks for at least 0.0625 in (1.6 mm) of space on each side of spine text, because the fold can drift slightly in binding.
  5. Low resolution. KDP asks for at least 300 DPI. A cover built at screen resolution looks fine on your monitor and prints soft. The PNG template is exactly 300 DPI, so artwork built on it is the right size.

We keep a page on each rejection with the exact KDP message and the fix: text in the bleed, spine too narrow, cover and trim size mismatch, barcode placement and low-resolution cover.

The barcode space

KDP’s barcode page suggests a space of 2 × 1.2 in (50.8 × 30.5 mm), placed at least 0.25 in (6.3 mm) from the spine and the trim. If you upload a cover without a barcode, KDP places one on the back cover for you, so leave that corner clear of text and faces. The template marks the space in the bottom corner beside the spine.

If you print your own barcode, KDP asks for 100% black on a solid white background, not a colour black.

Hardcover covers are different

The template above is for paperbacks. A KDP hardcover is a case laminate: the printed cover wraps round boards, so it has extra areas a paperback does not. From KDP’s Create a Hardcover Cover page, read 30 September 2026:

Hardcover areaKDP’s figure
Wrap, past the edge of the front cover0.51 in (KDP also writes 15 mm)
Hinge, between the spine and the safe area0.4 in (10 mm)
Keep text and images from the edge of the book0.635 in (16 mm)
Barcode2 × 1.2 in, at least 0.76 in (19 mm) from the bottom and 0.25 in (6 mm) from the hinge

KDP gives no formula for the hardcover spine; it sends authors to its own cover calculator. Several free tools publish one anyway. We don’t, because we can’t find it on any Amazon page. Use KDP’s template for a hardcover, and read hardcover vs paperback before you decide to make one.

Using the template in Canva, Affinity or Photoshop

  • Canva. Create a custom design at the pixel size shown above, upload the PNG and place it as the bottom layer. Canva exports print PDFs at 300 DPI when you choose “PDF Print”. Delete the template layer before exporting. Our Canva book cover guide covers the settings that trip people up.
  • Affinity or Photoshop. Open the PNG. It is tagged at 300 DPI, so the document comes in at the right physical size. Put your artwork on layers above it and hide the template before exporting a PDF.
  • Illustrator, Inkscape or InDesign. Use the SVG. It is drawn in inches at the exact cover size, so it places at 100%.

Frequently asked questions

How do I calculate the size of a KDP paperback cover?

Width is bleed + back cover + spine + front cover + bleed, and height is bleed + trim height + bleed, with 0.125 in bleed on each outer edge. The spine is the page count times 0.002252 in (white or standard colour), 0.0025 in (cream) or 0.002347 in (premium colour). The calculator above does it for any KDP trim size.

What size should a KDP cover be in pixels?

Multiply the size in inches by 300, KDP’s minimum resolution. A 6 × 9 in paperback with 250 white pages is 12.813 × 9.25 in, which is 3,844 × 2,775 pixels.

Where does the barcode go on a KDP cover?

On the back cover, in a space KDP suggests should be 2 × 1.2 in, at least 0.25 in from the spine and the trim. KDP adds a barcode there if your cover has none.

Can I put text on the spine?

Only on books with more than 79 pages, with at least 0.0625 in (1.6 mm) clear on each side of the text.

Does this work for hardcovers?

No, the template is for paperbacks. KDP does not publish a hardcover spine formula. The hardcover wrap, hinge and margin figures KDP does publish are in the table above.

Do I need a new cover if my page count changes?

Yes. Any change in page count changes the spine and the total width. Finish the interior first; our formatting service gives you the final page count before you brief a designer.

Put this calculator on your own site

Free, no sign-up, nothing to install. Paste this wherever you want it. It keeps working when Amazon changes its figures, because it reads from this page.

The embed carries a small credit line linking back here. That is the only condition, and it is the whole business model for a free tool.

Who made this. I am Robert Prime. I run publishing.co.uk, a UK formatting and cover service, so I build these wraps every week and read KDP's rejection emails when one goes wrong. Every figure on this page was read from Amazon's own KDP help pages on 30 September 2026, and the template is drawn from the same numbers the calculator prints, so the two cannot disagree. If KDP changes a figure, KDP is right: tell me and I will correct this page and say so.

Robert Prime — Founder of publishing.co.uk

About the Author

Robert Prime

Robert Prime is a best-selling self-published author, veteran eCommerce strategist, and the founder of publishing.co.uk. With over 25 years of experience in digital business he brings a battle-tested perspective to the publishing industry. After experiencing firsthand the archaic, headache-inducing process of formatting a KDP-compliant book for his own best-seller, Google. Panic. Repeat., Robert built publishing.co.uk to solve the problem for other authors. He is also a co-owner of the LoveReading.co.uk network (the UK’s leading book discovery platforms), founder of the Amazon growth agency MrPrime.com, and a member of the Forbes Business Council.