KDP Cover Size: How to Calculate Paperback Cover Dimensions & Spine Width
Quick answer: a 6×9 inch paperback with 200 pages on white paper needs a full cover of 12.700 × 9.250 in (spine 0.450 in). Get the exact size and a template for your book →
The KDP cover size formula
A paperback cover is one flat image: back cover, spine and front cover side by side, with bleed around the edges.
- Width = 0.125 in bleed + trim width + spine width + trim width + 0.125 in bleed
- Height = 0.125 in bleed + trim height + 0.125 in bleed
- Spine width = page count × paper thickness
Spine width per page
| Paper / ink | Thickness per page |
|---|---|
| Black & white, white paper | 0.002252 in |
| Black & white, cream paper | 0.0025 in |
| Standard color, white paper | 0.002252 in |
| Premium color, white paper | 0.002347 in |
Examples: 6×9 paperback
| Pages | Spine (white) | Full cover (white) | Spine (cream) | Full cover (cream) |
|---|---|---|---|---|
| 100 | 0.225 in | 12.475 × 9.250 in | 0.250 in | 12.500 × 9.250 in |
| 200 | 0.450 in | 12.700 × 9.250 in | 0.500 in | 12.750 × 9.250 in |
| 300 | 0.676 in | 12.926 × 9.250 in | 0.750 in | 13.000 × 9.250 in |
| 400 | 0.901 in | 13.151 × 9.250 in | 1.000 in | 13.250 × 9.250 in |
Page count must be the final number of pages in your interior PDF, including blank pages. If it changes, the spine and the cover width change too — check the page count estimator before you design.
Spine text and safe zones
- Spine text is allowed from 79 pages (Cover Creator needs 80).
- Leave at least 0.0625 in on each side of the spine text so it does not wrap onto the covers.
- Keep titles, author name and important art at least 0.125 in inside the trim line on the front and back.
- Leave room on the back cover for the barcode that KDP prints.
Common cover mistakes
- Designing the front cover only at 6×9 — KDP needs the full wrap-around cover.
- Using the wrong paper type — cream paper makes a wider spine than white.
- Forgetting the bleed — artwork must reach the outer edge of the full size.
- Low-resolution images — use 300 DPI.
Make your cover template free
The book cover size calculator works out the spine, the full cover size and the bleed for any trim size and page count, and draws a template with the spine and safe zones marked. For the inside pages, use the book bleed calculator.
Frequently asked questions
How do I calculate my KDP paperback cover size?
Width = 0.125 in bleed + trim width + spine width + trim width + 0.125 in bleed. Height = trim height + 0.25 in. For a 6×9 book with 200 white pages that is 12.700 × 9.250 in.
How wide is the spine on a KDP paperback?
Multiply the page count by the paper thickness: 0.002252 in per page for white paper, 0.0025 in for cream paper and 0.002347 in for premium color. 200 white pages = 0.450 in.
Can I put text on the spine?
KDP allows spine text from 79 pages (Cover Creator needs 80). Keep at least 0.0625 in of space on each side of the spine text.
What file does KDP need for the cover?
One PDF with the back cover, spine and front cover on a single page, at the exact full-cover size including bleed. Use 300 DPI images for sharp print.
