--- title: "KDP Cover Calculator: Spine Width and Cover Size" description: "Free KDP cover calculator: spine width and full cover size in inches, mm and pixels at 300 DPI, with a to-scale layout for paperbacks and hardcovers." url: https://podly.co/tools/kdp-cover-calculator/ --- [Free tools](https://podly.co/tools/) [Design & print](https://podly.co/tools/#design-and-print) # KDP cover calculator for spine width and full cover size This KDP cover calculator gives the spine width and full cover size in inches, millimeters and pixels, with a to-scale layout of the safe areas. Pick the binding, trim size, paper and page count. - Free - No signup needed - KDP specs checked November 2026 Binding Trim size Interior and paper Page count 24 to 828 pages. Use the final count of your interior PDF. Every KDP paperback cover has a 0.125 in (3.2 mm) bleed on the top, bottom and outside edges, whatever you chose for the interior. Paperback · 6 × 9 in · black ink, white paper Full cover size, inches 12.926 × 9.25 328.3 mm × 235.0 mm · 3,878 × 2,775 px at 300 DPI Bleed Trim line Safe area for text Drawn to scale **Spine width** 0.676 in 17.2 mm **Spine text** Allowed Keep it in 0.551 in **Pixels at 300 DPI** 3,878 × 2,775 Width × height, for your design file **Front safe area** 5.875 × 8.75 in 0.125 in inside the trim 1. Bleed 0.125 in 2. Back cover 6 in 3. Spine (300 pages × 0.002252") 0.676 in 4. Front cover 6 in 5. Bleed 0.125 in 6. Full cover width 12.926 in ## How we calculate this Paperbacks follow the formulas from KDP Help. KDP does not publish a hardcover formula, so for hardcovers we measured KDP's own cover calculator: the board is 5 mm wider and 6 mm taller than the trim, the wrap is 15 mm, and the spine is the page count × paper thickness + 0.189 in. Our results match KDP's calculator to the thousandth of an inch on every size we checked. **Spine width** page count × paper thickness **Paperback width** 0.125 + trim width + spine + trim width + 0.125 **Paperback height** 0.125 + trim height + 0.125 Pixels are rounded up at 300 DPI. Before you upload, download KDP's template for your exact book to check the barcode position. ![Podly Merch Database: filters for marketplace, product type, date, BSR, price and estimated sales above a grid of results](https://podly.co/images/home-v2/tab-research-1400.webp) Merch Database In Podly Your cover is sized. Is your niche worth it? Podly shows the rank, price and estimated sales of Amazon print-on-demand products, so you publish where buyers already are. [Start free](https://app.podly.co/register?utm_source=podly.co&utm_medium=website&utm_content=kdp_cover_calculator) Free plan · No credit card ## How to use the KDP cover calculator 1. Choose **Paperback** or **Hardcover**. 2. Pick your trim size. Paperbacks can also use a custom size from 4 to 8.5 in wide and 6 to 11.69 in tall. 3. Pick the interior: black ink on white, cream or groundwood paper, or standard or premium color. 4. Enter the final page count of your interior PDF. The spine depends on it, so set the cover last. 5. Create your design file at the pixel size shown, keep text inside the dotted safe areas, and leave the barcode area empty if KDP adds the barcode for you. ## KDP cover specs as of November 2026 | Paper | Spine per page | 300 pages | | --- | --- | --- | | Black ink, white paper | 0.002252 in (0.0572 mm) | 0.676 in | | Black ink, cream paper | 0.0025 in (0.0635 mm) | 0.75 in | | Black ink, groundwood paper | 0.00235 in (0.0596 mm) | 0.705 in | | Standard color | 0.002252 in (0.0572 mm) | 0.676 in | | Premium color | 0.002347 in (0.0596 mm) | 0.704 in | - **Bleed:** 0.125 in (3.2 mm) on the top, bottom and outside edges of every paperback cover. - **Safe area:** keep text 0.125 in inside the trim, and off the spine. - **Spine text:** paperbacks need at least 79 pages, with 0.0625 in (1.6 mm) clear on each side. - **Hardcover:** 15 mm wrap around the board and a 10 mm hinge next to the spine with no text or barcode. - **Barcode:** 2 × 1.2 in on the back cover. KDP places one for you if you do not. - **File:** one PDF, at least 300 DPI, 40 MB or less recommended. Sources, all on KDP: [Create a Paperback Cover](https://kdp.amazon.com/en_US/help/topic/G201953020), [Paperback Submission Guidelines](https://kdp.amazon.com/en_US/help/topic/G201857950), [Create a Hardcover Cover](https://kdp.amazon.com/en_US/help/topic/GDTKFJPNQCBTMRV6), [Print Options](https://kdp.amazon.com/en_US/help/topic/G201834180) and KDP's [cover calculator](https://kdp.amazon.com/en_US/cover-calculator). Checked on November 14, 2026. ## Worked example: a 6 × 9 paperback with 300 pages - Spine: 300 × 0.002252 in = 0.676 in (17.2 mm) - Width: 0.125 + 6 + 0.676 + 6 + 0.125 = 12.926 in - Height: 0.125 + 9 + 0.125 = 9.25 in - Design file at 300 DPI: 3,878 × 2,775 pixels Print the same book on cream paper and the spine grows to 0.75 in, so the cover is 13 in wide. That is why you cannot reuse a white-paper cover when you switch paper. ## Cover mistakes that get books rejected - **Sizing the cover before the interior is final.** Every 10 pages adds about 0.023 in to the spine. - **Spine text on a thin book.** Under 79 pages KDP rejects any text on the spine. - **Text right at the edge.** Up to 0.125 in can be trimmed off. Keep titles inside the safe area. - **Hard edges on the spine.** The spine can shift slightly in printing, so a sharp color change at the fold shows any shift. Next, check what you will earn with the [KDP royalty calculator](https://podly.co/tools/kdp-royalty-calculator/), or see which journals and planners sell in our guide to [selling journals on Amazon KDP](https://podly.co/blog/selling-journals-on-amazon-kdp/). Facts checked and page updated on November 14, 2026. ## KDP cover questions, answered. Something we missed? [Send us a message.](https://podly.co/contact/) A human answers. **01 What size should my KDP paperback cover be?** Back cover + spine + front cover, plus 0.125 in of bleed on the top, bottom and both outside edges. A 6 × 9 in paperback with 300 pages on white paper needs a 12.926 × 9.25 in cover, or 3,878 × 2,775 pixels at 300 DPI. **02 How do I calculate the spine width for KDP?** Multiply your page count by KDP’s paper thickness: 0.002252 in for white paper and standard color, 0.0025 in for cream, 0.00235 in for groundwood and 0.002347 in for premium color. 300 pages on cream paper give a 0.75 in spine. **03 How many pages do I need for spine text on KDP?** At least 79 pages for a paperback. Below that KDP rejects a cover with spine text. Leave 0.0625 in of space between the text and each fold of the spine. **04 Is a KDP hardcover cover the same size as the paperback?** No. A hardcover file adds a 15 mm wrap that folds around the boards, the boards are slightly larger than the trim, and the spine is wider. A 6 × 9 in hardcover with 300 pages needs a 14.439 × 10.417 in file. **05 What resolution does a KDP cover need?** At least 300 DPI, saved as one PDF with the back cover, spine and front cover together. KDP recommends 40 MB or less and does not convert files over 650 MB. More free tools ## Keep going with these free tools. - Calculators ### KDP royalty calculator Printing cost and royalty for your book - Design & print ### DPI calculator Print size and DPI from your pixel size - Design & print ### Pixels to inches Convert pixels and inches at any DPI Free ebook ## +1,000 Print-On-Demand niches. Free, in your inbox. More than 1,000 hot Print-On-Demand niches, updated weekly. Discover top-selling ideas and start getting more sales. [See what's in the guide](https://podly.co/1100-free-niche-for-merch-by-amazon/). ![The 1,000+ Niches That Sell ebook standing in the clouds](https://podly.co/images/home-v2/ebook.webp) ## Cover ready. Now find books and designs that sell. Join 6,000+ Merch sellers who check Podly before they design. [Start free, find best-sellers](https://app.podly.co/register?utm_source=podly.co&utm_medium=website&utm_content=kdp_cover_calculator_final) [Add to Chrome, free](https://chromewebstore.google.com/detail/podly-ai-toolset-for-merc/dipicnapjjmogjmpcncbfooffdhcfndk) ![Podly Merch Database](https://podly.co/images/home-v2/tab-research.webp)