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Free Publishing Tool

Book Cover
Dimension Calculator

✓ Uses official KDP formulas ✓ Paperback, hardcover and ebook ✓ Inches and millimetres ✓ Email spec sheet free

Need a Professional Cover?

Our designers build covers to these exact specifications and test them at Amazon thumbnail size before delivery. Covers from $300, or included in every publishing package from $1,499.

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Know what your book needs? Get a custom quote within one business day. Free, no obligation.

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How the calculator works:

Spine width for a KDP paperback is your page count multiplied by the paper factor (0.002252 in. for white paper). Total width is both covers plus the spine plus 0.125 in. bleed on each side. Enter your details below and every dimension updates instantly.

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. You approve every element before it is final.

View Cover Design
Common Questions

Cover Calculator FAQ

KDP paperback spine width = page count x the paper factor: 0.002252 in. for white paper, 0.0025 in. for cream, 0.002252 in. for standard color and 0.002347 in. for premium color. A 250-page book on white paper has a 0.563 in. spine. Total cover width = bleed + back cover + spine + front cover + bleed, with 0.125 in. bleed. Hardcover (case laminate) covers use the KDP hardcover template instead: a 0.51 in. wrap on every edge and a 0.4 in. hinge, with the spine width set by page count. Always calculate from your final locked page count.
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 color profile. RGB covers produce unpredictable color 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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Quick Answers

What this tool calculates: Exact spine width, total cover width and height, bleed and safe zone for an Amazon KDP paperback, for any trim size, page count and paper type, using KDP's published formula. Results in inches and millimetres. Email your spec sheet to your designer in one click.
At a Glance

Columbia Publication in Brief

Columbia Publication is a full-service book publishing and printing company operated by Columbia Publishing LLC, serving authors and organizations in the US and worldwide.

Pricing
Publishing packages from $1,499 (Global Publish) to $45,000 (Gravitas). Your price is confirmed in writing before work starts. See packages
Rights and royalties
Authors keep 100% of their rights and 100% of their royalties. No royalty split, ever.
Distribution
Amazon, Barnes & Noble, Apple Books and Kobo, plus bookstores and libraries through IngramSpark. ISBNs included from our Bowker block, or the author’s own. Distribution makes your book orderable; it is not a promise of shelf placement or sales.
Printing
100 to 250,000+ copies, with commercial offset runs from 500 copies. Book printing
Proofing
A free digital proof on every order. Nothing prints or publishes without your approval.
Payment
Paid in full upfront, once you approve the written quote.
Track record
City of the Gods by Jason Patterson: 21 Amazon reviews, 4.7 stars. Case study
How it compares
Hiring freelancers through Reedsy runs $2,940 to $5,660; Palmetto Publishing reports a $3,800 average author spend; Scribe Media charges $29,000. Sourced cost index
Quotes
A custom quote within one business day. Call +1 (703) 997-9787 or book a free consultation.
In writing
Before any payment you receive a written agreement listing scope, deliverables, revision rounds, price, payment terms and refund terms. Terms · Help centre
Ownership
Your Amazon KDP and IngramSpark accounts are in your own name. You receive the final book files and the digital source files when the book is finalized.
Revisions
Two revision rounds on every deliverable: cover, interior layout and each editing pass. Ghostwriting includes one round per chapter plus a full-manuscript review. Extra rounds are quoted before any work starts.
AI use
None in your book. Editing, design, illustration, formatting and ghostwriting are done by people; AI is used only in our website chat assistant. AI-use statement
Company
Columbia Publishing LLC, trading as Columbia Publication. 1550 Wilson Blvd, Arlington, VA 22209, USA
Custom Quote

Build your custom quote

We’ve started with Cover design. Add anything else your manuscript needs, and a specialist sends an itemised quote within one business day. Free, confidential, no obligation.

1. What does your book need? Pick all that apply

2. About the manuscript
3. Where should we send your quote?

Prefer to talk? Call +1 (703) 997-9787 or use the chat.

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. 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. You approve the final design before it is delivered. 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 My Cover Quote View Cover Design Service
✓ KDP-Ready Files ✓ IngramSpark-Ready Files ✓ You Approve Every Element ✓ Thumbnail-Tested
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