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KDP Cover Calculator
Your KDP paperback cover is two trim-size panels plus the spine plus 0.125 in bleed on every outer edge; the spine is your page count times the paper thickness (0.002252 in per page on white paper). For a 6 × 9 in book with 240 white pages that is a 0.540 in spine and a 12.790 × 9.250 in cover, or 3837 × 2775 px at 300 DPI.
- Spine width
- 0.540 in13.7 mm · 162 px
- Full cover width
- 12.790 in324.9 mm · 3837 px
- Full cover height
- 9.250 in234.9 mm · 2775 px
- Spine text
- AllowedKeep it 0.0625 in from each fold
- Front / back panels
- 6 × 9 inplus 0.125 in bleed on the outer edges
How to use it
- Pick your trim size. The size you chose in KDP’s paperback setup, e.g. 6 × 9 in.
- Enter the final page count. Use the count of the interior you will upload, including blank pages. KDP counts every page.
- Choose paper and ink. Cream paper is thicker than white, so it changes the spine.
- Design to the full-cover size. Use the width and height above (or download a ready template) and keep text inside the safe zones.
The formula
Spine = page count × paper thickness. Cover width = 0.125 + trim width + spine + trim width + 0.125 in. Cover height = 0.125 + trim height + 0.125 in.
| Paper & ink | Thickness per page | 240 pages |
|---|---|---|
| Black ink, white paper | 0.002252 in | 0.540 in |
| Black ink, cream paper | 0.0025 in | 0.600 in |
| Standard color, white paper | 0.002252 in | 0.540 in |
| Premium color, white paper | 0.002347 in | 0.563 in |
Want a file to design on? The free KDP cover template generator draws these guides at print size. Already have front artwork? Upload your interior and we build the whole wrap — back, spine and front — with the spine width taken from your actual page count.
Source: KDP Help: Create a Paperback Cover. Checked .
When to use it
- Paperback covers for KDP print, any trim size from 5 × 8 to 8.5 × 11 in
- Checking a designer’s cover file before you upload it
- Re-sizing a cover after your page count changed
When not to
- Hardcover case laminate covers: they need wrap and hinge allowances (coming soon)
- eBook covers: those are a single front image, 2560 × 1600 px recommended
At a glance
- Free: full check report, cover/spine calculator, royalty calculator. No account needed.
- Paid: $9 per book, one-time — fixed interior PDF + full-wrap cover (PDF, PNG, layered PSD). Re-download for 30 days.
- Files are processed in your browser; your manuscript is never uploaded to our servers.
- Pagination never changes; text is scaled uniformly (default keeps ≥ 0.08″ clearance inside KDP's margins).
- Supports paperback, no-bleed interiors, trim sizes 5×8 to 8.5×11, 24–828 pages. Bleed (picture books) and hardcover: coming soon.
- Refund: if KDP rejects a problem we fixed, full refund.
- Not affiliated with Amazon. KDP's previewer is the final authority.
FAQ
How do I calculate the spine width for a KDP paperback?
Multiply the page count by the paper thickness: 0.002252 in per page for white paper (black or standard color ink), 0.0025 in for cream paper and 0.002347 in for premium color. A 240-page book on white paper has a 0.540 in spine.
What size should my full KDP cover be?
Width = 0.125 in bleed + back cover width + spine + front cover width + 0.125 in bleed. Height = trim height + 0.25 in (0.125 in bleed top and bottom). A 6 × 9 in book with 240 white pages needs a 12.79 × 9.25 in cover.
How many pixels is a KDP cover?
At 300 DPI, multiply each inch measurement by 300. A 12.79 × 9.25 in cover is 3837 × 2775 pixels. KDP needs at least 300 DPI for print.
Can I put text on the spine?
KDP’s help page allows spine text from 79 pages, which means 80 or more for a printed book (page counts are even). Keep it at least 0.0625 in from each fold so it doesn’t wrap onto the front or back.
Where does the barcode go?
KDP prints the ISBN barcode in a 2 × 1.2 in box in the bottom right of the back cover, 0.25 in from the trim edges. Keep that area empty unless you supply your own barcode.
Does the spine width change if I change paper?
Yes. Cream paper is thicker than white, so the same 240 pages give a 0.600 in spine on cream versus 0.540 in on white. Recalculate whenever you change paper or page count.