How the KDP bleed calculator separates page size, bleed and gutter
Use the KDP bleed calculator to plan one paperback interior page from its finished trim width and height. With bleed, add 0.125 inch to the outside width and 0.125 inch at both the top and bottom. A 6 × 9 inch trim therefore needs a 6.125 × 9.25 inch page. Without bleed, the file page equals the finished trim. Neither result describes the separate back–spine–front cover.
The binding edge gets no additional bleed. On a right-hand page, the outside edge is on the right; on a left-hand page, it is on the left. Mirror the inside gutter accordingly. Bleed carries artwork beyond the cut, while the gutter keeps important content away from the binding. With bleed, the minimum top, bottom and outside margins are 0.375 inch from the file edge, leaving 0.25 inch inside the trim.
Production pages determine the gutter and listed paper limits. Count blank pages and round an odd manuscript count upward to an even number: 151 becomes 152. Its minimum gutter is 0.5 inch rather than the 0.375 inch used through 150 pages. Standard color starts at 72 production pages; the other listed paper options start at 24. Maximums depend on the selected trim and paper.
For raster planning, multiply each physical page dimension by 300. The exact result can contain a fraction; a pixel canvas cannot. This tool shows the exact arithmetic and rounds each suggested canvas dimension upward. The final PDF must still use the exact inch dimensions. Neither the diagram nor the pixel suggestion inspects your manuscript, embeds fonts or establishes printing acceptance.
With bleed: W = trim width + 0.125 in; H = trim height + 0.25 in. Exact pixels = inches × 300. Suggested whole pixels = ceil(exact pixels).
Set up and check a single-page paperback interior
Choose paperback and the finished trim, ink and paper used in your book setup. Enter the final manuscript count, including blanks, and check the even production count before choosing a gutter. Paper and page count can change eligibility even when dimensions stay unchanged. Hardcover uses separate specifications and receives no result here.
Second, decide whether any artwork reaches a cut edge. If one page needs bleed, prepare the interior using the bleed setup rather than mixing differently sized pages. Extend that artwork to the enlarged outer edge, not merely to the trim line. Keep text, page numbers and essential diagram labels within the safe area. On facing pages, confirm that the gutter lies beside the binding on both sides.
Third, enter exact physical page dimensions in the design application. For a 6 × 9 inch bleed interior, use 6.125 × 9.25 inches. If an image editor requires integers, the 1838 × 2775 suggested canvas avoids rounding below the 300 PPI target. Place that raster at the intended physical size. Changing a density tag cannot add pixels or make a low-detail image suitable for a larger placement.
Fourth, handle custom trims explicitly. The accepted finished bounds are 4–8.5 inches wide and 6–11.69 inches high, with up to four decimal places. A custom entry matching a listed preset inherits that preset’s limits. Other custom combinations provide geometry with an unknown maximum and unverified eligibility. Confirm those combinations in KDP before formatting a complete book; the tool’s 24–828 input range is not a universal custom-production allowance.
Finally, export single PDF pages and inspect the exported document. Check every page’s size, sequence, margins and edge artwork, including chapter openings and blanks. Remove layout guides and crop marks and check font embedding in your export application. Use KDP Print Previewer to inspect the actual file. A saved calculation link contains settings, not a manuscript review; its query values may appear in browser history and request logs when shared.
Paperback interior dimensions and minimum-margin reference
This table combines implemented page geometry with the production-page gutter bands. Dimensions are inches unless pixels are named. Bleed is added only to the top, bottom and outside; the binding edge receives none. Pixel values belong to the stated physical page and use 300 PPI arithmetic. The 6 × 9 bleed width produces half a pixel, so its suggested raster width is 1838 rather than 1837.
Read the gutter rows using the normalized production count, not the number printed on the last numbered page. A manuscript with 301 pages becomes 302 production pages and belongs in the 0.625 inch band. The margin rows measure from the manuscript file edge; their difference is the 0.125 inch bleed strip. A larger margin is a design choice, while the table records the minimum used by the calculator.
| Setting | Value | How to use it |
|---|---|---|
| 6 × 9, no bleed | 6 × 9 in | 1800 × 2700 pixels at 300 PPI |
| 6 × 9, with bleed | 6.125 × 9.25 in | Exact 1837.5 × 2775; suggest 1838 × 2775 |
| Bleed at each cut edge | 0.125 in | Top, bottom and outside only |
| 24–150 production pages | 0.375 in gutter | Inside margin beside binding |
| 151–300 production pages | 0.5 in gutter | Inside margin beside binding |
| 301–500 production pages | 0.625 in gutter | Inside margin beside binding |
| 501–700 production pages | 0.75 in gutter | Inside margin beside binding |
| 701–828 production pages | 0.875 in gutter | Inside margin beside binding |
| Outside/top/bottom, no bleed | 0.25 in minimum | Measured from file edge |
| Outside/top/bottom, with bleed | 0.375 in minimum | Measured from file edge |
Three KDP bleed calculator examples with exact dimensions
These planning examples use even production counts for the gutter. Preserve exact physical PDF dimensions rather than replacing them with rounded pixels. Check preset paper limits; the custom example does not establish production eligibility.
Example 1: 6 × 9 inches, 150 pages, with bleed
Width is 6 + 0.125 = 6.125 inches; height is 9 + 0.25 = 9.25 inches. At 300 PPI, multiply to obtain 1837.5 × 2775 exact pixels and use 1838 × 2775 for the suggested integer canvas. The 150-page gutter is 0.375 inch. On a right-hand page, the safe horizontal width is 6.125 − 0.375 − 0.375 = 5.375 inches; safe height is 9.25 − 2 × 0.375 = 8.5 inches. Mirror the gutter for a left-hand page.
Example 2: 8.5 × 11 inches, 151 manuscript pages, no bleed
The production count is ceil(151 ÷ 2) × 2 = 152 pages. With no bleed, the page stays 8.5 × 11 inches and the canvas arithmetic is 2550 × 3300 pixels. The minimum gutter becomes 0.5 inch. Outside, top and bottom margins are each 0.25 inch, giving a safe width of 8.5 − 0.5 − 0.25 = 7.75 inches and height of 11 − 0.5 = 10.5 inches. Select an eligible paper and confirm its listed range.
Example 3: custom 7.125 × 9.5 inches, 301 pages, with bleed
The page becomes 7.25 × 9.75 inches. Multiplication by 300 gives 2175 × 2925 pixels, so no pixel rounding is needed. The manuscript becomes 302 production pages, with a 0.625 inch gutter. Two page files side by side have a 14.5 × 9.75 inch reference footprint. Submit two separate 7.25 × 9.75 pages, not that spread. This unlisted custom combination remains geometry-only: its maximum page count and production eligibility need confirmation in KDP.
Avoid page-size and binding-edge mistakes
Do not add 0.125 inch to both horizontal edges of an interior page. That would make a 6 inch trim 6.25 inches wide, whereas this bleed rule requires 6.125. Full-cover bleed follows a different layout because a cover spans back, spine and front. Reusing cover dimensions for an interior produces the wrong manuscript canvas.
Do not round 1837.5 pixels down and then describe the result as an exact 300 PPI width at 6.125 inches. Use the stated whole-pixel suggestion and keep the PDF’s physical size explicit. Likewise, a metadata-only conversion cannot repair blurry source artwork, an incorrect PDF page size or text sitting too close to the cut.
Check all pages after copying a layout. A mirrored gutter can be correct on one page and wrong on the next. Avoid placing a face or essential label across the binding; the facing-page reference cannot predict how much detail will be difficult to see there. After the interior and production count are final, prepare the separate cover using the same trim, paper and count. Changing those inputs later requires another cover calculation.
Five questions about paperback bleed and export
01What size does a 6 × 9 inch paperback need with bleed?
Use 6.125 × 9.25 inches per PDF page. Add 0.125 inch at the outside, top and bottom, with none at the binding. Exact 300 PPI arithmetic gives 1837.5 × 2775 pixels; the suggested canvas is 1838 × 2775. Retain the exact physical PDF dimensions.
02Can I use the facing-page reference as my upload file?
No. The reference shows two mirrored page files for planning artwork direction. A 6 × 9 bleed pair occupies 12.25 × 9.25 inches, but submission requires separate single pages. Export each at 6.125 × 9.25 inches and inspect sequence, gutters and bleed.
03Does a custom trim result confirm that KDP will print it?
No. A listed-size match uses its preset limits. Other custom trims provide geometry with unverified eligibility and an unknown maximum count. Accepted input bounds do not establish every paper and page combination. Confirm the specific trim, paper and count in KDP before formatting.
04Why does an odd page count sometimes increase the gutter?
Manuscript pages round upward to an even production count before applying gutter bands. Thus 151 becomes 152 and uses 0.5 inch, while 150 uses 0.375. Include blank pages and use the final exported count when calculating the separate cover’s spine.
05Will correct dimensions guarantee acceptance or improve image detail?
No. The calculator does not inspect PDF content, image sharpness or font embedding. Check the exported pages in KDP Print Previewer, including edge artwork, margins and orientation. A 300 DPI metadata tag changes print scale; it cannot supply an undersized image’s missing pixels.