KDP Cover Sizes Explained
A KDP paperback cover is your trim size plus the spine width plus bleed, exported at 300 DPI. The spine grows with your page count, so the full-cover size is different for every book — the figures below are the ones Amazon publishes, and the mockup tool previews your front cover free.
Trim size + spine + bleed
A full KDP paperback cover is made of three things: the trim size (your finished book’s width and height), the spine width (which grows with your page count and paper type), and bleed on the outer edges. Because the spine depends on your exact page count, the full-cover dimensions are different for every book.
The front cover on its own is simpler, and it is the part you need for a thumbnail, an ad or a mockup. At the most common paperback trim it works out to the size in the table below.
| Use case | Size | Aspect | Notes |
|---|---|---|---|
| Paperback front cover, 6″×9″ trim | 1800×2700px · 300 DPI | 2:3 | Front cover only at 300 DPI. The full wrap (back + spine + front) depends on page count — use the KDP cover calculator. |
Verified 2026-06-13 against the official KDP paperback cover guidelines.
The numbers Amazon publishes
These are the fixed requirements from Amazon’s paperback cover help page — they do not change with your book, so you can set them once in your design file.
| Requirement | Value | Notes |
|---|---|---|
| Resolution | 300 DPI | Minimum for the whole cover PDF. Below this, print gets soft. |
| Bleed | 0.125″ (3.2 mm) | Added to the top, bottom and outside edges of the cover. |
| Text safe margin | 0.125″ (3.2 mm) | Keep front and back cover text at least this far inside the trim lines. |
| Minimum pages for spine text | 79 | Books under this page count cannot carry text on the spine. |
| Spine text margin | 0.0625″ (1.6 mm) | Clear space needed on either side of spine text. |
| Spine width, white paper | × 0.002252″ | Multiply your page count by this figure to get the spine width. |
| Minimum font size | 7 pt | Amazon’s readability floor for cover text. |
| Maximum file size | 650 MB | Cover PDF upload limit; 40 MB or less is recommended. |
Verified 2026-09-06 against Amazon’s official paperback cover requirements. For the full wrap including your own spine width, use the KDP cover calculator.
Preview your cover free
Upload your front cover and see it as a paperback or hardcover — clean PNG, no watermark, no signup.
Want a 3D render for your launch graphics? We compared the free book cover mockup generators — which ones export a transparent PNG, and which want an account.
FAQ
What determines a KDP paperback cover size?
A KDP paperback cover is your trim size (the finished book dimensions) plus the spine width — which depends on your page count and paper type — plus bleed on the outer edges. Amazon provides an official cover calculator that outputs the exact full-cover dimensions for your book.
How wide is the spine on a KDP paperback?
On white paper, Amazon calculates the spine as your page count multiplied by 0.002252 inches. A 300-page paperback on white paper therefore has a spine about 0.68 inches wide. Cream and colour paper use different multipliers, and books under 79 pages cannot have text on the spine at all.
How much bleed does KDP need?
Amazon asks for 0.125 inches (3.2 mm) of bleed on the top, bottom and outside edges of the cover. Cover text should also sit at least 0.125 inches inside the trim lines, so nothing important is lost when the book is cut.
How do I preview my cover before publishing?
Upload your front cover to our book cover mockup generator and download a clean 1x PNG — no watermark, no signup — to check how it reads as a thumbnail before you publish.
Does the mockup tool change my print file?
No. The generator only creates a preview image; it never touches or uploads your real print-ready PDF. Use Amazon’s cover calculator for the exact print dimensions.