KDP Editor – free KDP interior editor, margin fixer and bleed tool
KDP Editor is a free, in-browser KDP interior editor for Amazon KDP authors – especially coloring books, activity books and picture books. Load your whole interior PDF, see every page against KDP’s trim, bleed and margin guides, fix “image outside the margins” errors, then crop, move, scale or rotate each page and export everything as one print-ready PDF. KDP’s Print Previewer only shows the problems; KDP Editor lets you fix them.
🔒 Your PDF never leaves your computer. All processing happens locally in your browser – nothing is uploaded, there is no account and there are no trackers.
How to fix KDP margin and bleed errors in 4 steps
- Open your interior PDF (button “Open PDF” or drag & drop). The trim size and bleed are detected from the first page – check them in the left panel.
- Find the flagged pages. Pages whose content crosses the safe area get a red “!” and red stripes – the same pages KDP marks with “This image is outside the margins”.
- Fix them with one click (“Fix flagged pages”), or page by page: drag to move, use the crop handles, change the scale, “Fit to margins”, or “Fill with bleed” for full-page art. “Apply to all pages” copies one page’s layout to the rest (mirrored for left/right pages).
- Export PDF for KDP and upload the new file as your manuscript in KDP. Reorder, duplicate, insert blank or delete pages before export if needed.
Step-by-step with causes and screenshots of the problem: How to fix “image outside the margins” on KDP.
What KDP Editor does
- KDP margin fixer – detects content in the margin zone on every page and scales or moves it into the safe area, with the inside (gutter) margin set automatically from the page count.
- KDP bleed tool – switch an interior between bleed and no bleed; the page size changes to trim + 0.125 in wide and + 0.25 in tall, and “Fill with bleed” stretches full-page art past the trim line.
- Trim size change – re-lay out a whole PDF to any KDP trim size (for example 8.5 × 11 in to 8.5 × 8.5 in) without going back to your design program. See all KDP trim sizes.
- Page tools – crop, rotate, reorder, duplicate, insert blank pages, merge several PDFs, undo/redo, save the layout as a project file.
- Sharp output – vector export keeps your line art untouched; an optional 300 DPI raster export trims each page image exactly to the visible content.
Amazon KDP paperback margin requirements
The inside (gutter) margin depends on the page count; outside, top and bottom margins depend on whether your book has bleed.
| Page count | Inside margin |
|---|---|
| 24 – 150 | 0.375 in (9.6 mm) |
| 151 – 300 | 0.5 in (12.7 mm) |
| 301 – 500 | 0.625 in (15.9 mm) |
| 501 – 700 | 0.75 in (19.1 mm) |
| 701 – 828 | 0.875 in (22.3 mm) |
| Book | Minimum |
|---|---|
| Without bleed | 0.25 in (6.4 mm) |
| With bleed | 0.375 in (9.6 mm) |
With bleed, the PDF page must be 0.125 in (3.2 mm) wider and 0.25 in (6.4 mm) taller than the trim size – e.g. an 8.5 × 8.5 in coloring book becomes 8.625 × 8.75 in. Source: KDP Help – Set Trim Size, Bleed, and Margins. Always double-check the current KDP rules before publishing. Worked examples and safe-area sizes: KDP margins and bleed guide.
Guides
- KDP margins and bleed guide – exact minimums, page size with bleed, safe area examples.
- Fix “image outside the margins” on KDP – why KDP flags pages and how to fix every cause.
- KDP trim sizes – every paperback and hardcover size, page size with bleed and page-count limits.
FAQ
What is KDP Editor?
KDP Editor is a free web app that edits the layout of an existing KDP interior PDF: it checks every page against Amazon KDP’s trim, bleed and margin rules, fixes pages that are outside the margins, changes trim size or bleed, and exports one corrected PDF. It runs entirely in your browser.
Why does KDP say “This image is outside the margins”?
KDP’s Print Previewer checks whether any content (text, line art, or the bounding box of an image) reaches into the margin zone or past the trim. Coloring-book pages often have frames or artwork that go almost to the edge, so every such page is flagged. Scaling the artwork down into the safe area – or extending it fully into the bleed – fixes it.
Do I need bleed for a coloring book?
Only if the artwork should print all the way to the edge of the paper. Most coloring books use no bleed and keep the art inside the margins. If you enable bleed, content must either stay inside the safe area or extend past the trim into the bleed – nothing important should sit in between.
Is my PDF uploaded anywhere?
No. KDP Editor is a static web page: PDF reading (pdf.js) and PDF writing (pdf-lib) run entirely in your browser. You can even use it offline once the page has loaded.
Will exporting reduce the quality of my pages?
The default vector export embeds your original pages unchanged and only scales and clips them, so line art stays perfectly sharp. The optional raster export renders each page at 300 DPI.
KDP still flags a page after I fixed it – what now?
Some files contain a large invisible or white image behind the artwork. KDP measures the whole image, even if most of it is clipped. Switch the export to “Raster 300 DPI, trimmed to content”: each page image then ends exactly at the visible content. You can also raise the margins slightly or the “Fit padding”.
Is this an official Amazon tool?
No. KDP Editor is an independent, free tool and is not affiliated with or endorsed by Amazon. Kindle Direct Publishing and KDP are trademarks of Amazon.com, Inc. or its affiliates.