KDP Cover Size Calculator & Cover Template Generator
Get the exact full-wrap cover size, spine width and a printable cover template for your KDP paperback, using Amazon KDP's own published formula. Free, no sign-up.
Use the page count from your final, formatted interior PDF — Word or Google Docs page counts are often different.
How KDP works out your cover size
Amazon KDP prints your paperback cover as one piece that wraps around the book: back cover, spine and front cover, plus a little extra on every edge (the bleed) that gets trimmed off. KDP's formula is:
Cover width = 0.125" bleed + back cover width + spine width + front cover width + 0.125" bleed
Cover height = 0.125" bleed + trim height + 0.125" bleed
So a 6" x 9" book is always 9.25" tall, and 12.25" wide plus the spine.
KDP spine width by paper type
| Paper | Spine width per page | 200 pages | 300 pages |
|---|---|---|---|
| White (black & white) | 0.002252" | 0.450" | 0.676" |
| Cream (black & white) | 0.0025" | 0.500" | 0.750" |
| Standard color | 0.002252" | 0.450" | 0.676" |
| Premium color | 0.002347" | 0.469" | 0.704" |
Cream paper is thicker than white, so a cover built for white paper but printed on cream comes out with a spine that's too narrow, one of the most common reasons a cover gets rejected or the spine art wraps onto the front.
Spine text rules
- KDP only prints spine text on books with more than 79 pages.
- Keep spine text at least 0.0625" away from each fold line. KDP allows that much movement when it folds the cover.
Other things that get KDP covers rejected
- No bleed: background art must reach all the way to the outer edge of the template, not stop at the trim line.
- Text too close to the edge: titles or names sitting in the trim zone get cut off.
- Low-resolution images: photos under 300 DPI print blurry.
- Wrong file size: a cover PDF that doesn't match the exact size above is rejected automatically.
Already have your cover and interior?
SparkPrep checks your actual files against KDP's and IngramSpark's rules: size, bleed, spine, ink, image resolution, fonts and more. It shows you exactly what's wrong in plain English and fixes it for you, before you upload. It was built by an author whose book was rejected 18 times.
Check my book files with SparkPrep Spine width calculatorMore free tools
- Book spine width calculator (KDP & IngramSpark)
- Book cover dimensions for every common book size
- IngramSpark cover template: how to get it right
- IngramSpark rejection messages explained (and how to fix them)
Numbers on this page come from Amazon KDP's own help pages for paperback covers. Always do a final check with KDP's cover calculator before you upload. SparkPrep is an independent tool and is not affiliated with Amazon or IngramSpark.