How to use the KDP Cover Size Calculator
- Pick your trim size (6 × 9 in is the most common).
- Enter your final page count and choose the interior ink and paper.
- Read the spine width and full cover size, including 0.125″ bleed.
- Download the 300 DPI template and design your cover on top of it.
About this tool
A KDP paperback cover is one image that wraps around the back, spine and front of the book. Its width depends on your trim size and on the spine, which depends on the page count and paper thickness.
Formulas used (from KDP)
- Spine width = page count × paper factor: 0.002252″ white paper, 0.0025″ cream paper, 0.002347″ premium color.
- Cover width = bleed + back cover + spine + front cover + bleed (bleed = 0.125″).
- Cover height = bleed + trim height + bleed.
Example: a 250-page, 6 × 9 in book on white paper has a 0.563″ spine and a full cover of 12.813″ × 9.25″ (3,844 × 2,775 px at 300 DPI).
Design tips
- Keep titles and important text at least 0.125″ inside the trim lines.
- Spine text is only allowed on books with 79 or more pages.
- Export your final cover as a PDF at 300 DPI, and always check it with KDP’s previewer.
Frequently asked questions
How do I calculate KDP spine width?
Multiply the page count by 0.002252 inches for white paper or 0.0025 inches for cream paper (0.002347 for premium color).
What bleed does KDP require for covers?
0.125 inches (3.2 mm) on every outside edge.
How many pages do I need for spine text?
At least 79 pages.
What resolution should my cover be?
300 DPI. The calculator shows the exact pixel size you need.