Free Publishing Tool

Book Cover
Dimension Calculator

What this tool calculates: Exact spine width, total cover width and height, bleed dimensions and safe zone for Amazon KDP and IngramSpark — for any trim size, page count and paper type. Results in inches and millimetres. Email your spec sheet to your designer in one click.
✓ Uses official KDP formulas ✓ KDP + IngramSpark outputs ✓ Inches and millimetres ✓ Email spec sheet free

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Enter Your Book Details

Results update instantly. All fields required for print books.

Must be between 24 and 828 pages for this trim size
Paste directly into a brief for your designer
How to Use These Numbers

What to Do with Your Cover Dimensions

Once you have your exact cover dimensions, here is exactly how to use them at each stage of production.

1

Send to your cover designer

Your designer needs the total cover width, total cover height, spine width and bleed to set up their document correctly. Use the "Copy Spec Sheet" button or email the spec to yourself and forward it. Every dimension in this tool is what your designer needs to start work.

2

Lock your page count first

The spine width changes with every page you add or remove from your interior. Always complete and lock your interior formatting before building or commissioning a cover. A 10-page change at the wrong moment means a new cover file. See the KDP formatting guide for interior specifications.

3

Build separate files for KDP and IngramSpark

If publishing to both platforms, you need two cover PDFs with platform-specific dimensions. The design is identical — the canvas size and spine width differ. Use this calculator for KDP dimensions, then use IngramSpark's own template generator for their version.

4

Keep all text in the safe zone

The safe zone is 0.25 inch inside the trim line on all sides. Title, author name, spine text and back cover copy must all sit inside this zone. The bleed area outside the trim line is for backgrounds and images only — anything inside it risks being cut off during printing.

Want the cover built to these specifications?

Columbia Publication designs covers to KDP and IngramSpark specifications, tested at thumbnail size before delivery. Unlimited revisions.

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Common Questions

Cover Calculator FAQ

KDP spine width formulas: White paper = (page count × 0.002252) + 0.06 inches. Cream paper = (page count × 0.0025) + 0.06 inches. Colour paper = (page count × 0.002347) + 0.06 inches. For hardcover, add 0.3 inch for the case wrap. This calculator applies these formulas automatically. Always calculate from your final locked page count — never an estimate.
Amazon KDP requires 0.125 inch (3.175mm) bleed on all four sides of the cover PDF. This applies to all binding types and trim sizes without exception. Cover bleed is always required regardless of the cover design, even if the background is solid white.
The safe zone is 0.25 inch (6.35mm) inside the trim line on all four sides of the cover. All critical text, logos and design elements must stay within this safe zone to avoid being cut off during printing. The bleed area between the trim line and the edge of the file is for backgrounds and images only.
Amazon KDP recommends eBook cover images at 2,560 x 1,600 pixels with a height-to-width ratio of 1.6:1. The minimum accepted size is 1,000 x 625 pixels. Files should be saved as JPEG or TIFF at the highest quality setting. eBook covers are front-cover only — no spine or back cover is required.
Yes. IngramSpark uses slightly different spine width calculations from KDP. If publishing to both platforms, build two separate cover files using platform-specific dimensions. Use this calculator for KDP dimensions, and IngramSpark's own cover template generator for IngramSpark dimensions. The design is identical — only the file canvas size and spine width differ between platforms.
Print covers (paperback and hardcover) must be CMYK colour profile. RGB covers produce unpredictable colour shifts when printed. eBook front covers should be RGB. Resolution must be 300 DPI minimum at the final print size, with 600 DPI recommended for covers.
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Want Your Cover Built to These Exact Specifications?

Columbia Publication builds every cover to exact KDP and IngramSpark specifications, ensuring your files pass platform review on the first upload. Each design is dimensionally precise, preflighted for both retail channels, and thumbnail-tested at Amazon display size before delivery. Unlimited revisions are included, and you can schedule a free consultation with no obligation to begin.

Columbia Publication builds every cover to exact KDP and IngramSpark specifications, so your files pass review on the first upload. Each design is dimensionally accurate, preflighted for both platforms, and thumbnail-tested at Amazon display size before delivery. Unlimited revisions ensure the final result meets your standards. Schedule a free consultation to get started.

Columbia Publication designs covers preflighted to KDP and IngramSpark specifications — every dimension correct, tested at Amazon thumbnail size before delivery. Free consultation with no obligation.

Get a Free Publishing Consultation View Cover Design Service
✓ KDP-Ready Files ✓ IngramSpark-Ready Files ✓ Unlimited Revisions ✓ Thumbnail-Tested
Columbia Publication — 1550 Wilson Blvd, Arlington, VA 22209, USA — support@columbiapublication.com