How It Works

Three steps to verify your book is KDP-ready

Upload

Drag and drop or browse to select your PDF interior file.

Select Specs

Choose your intended trim size, content type, and bleed setting.

Check

Get an instant, detailed report of all KDP specification checks.

Why Use Our Preflight Checker

Catch issues before you upload to KDP

⚡ Instant Results

Your PDF is parsed entirely in your browser. No upload to any server, no waiting. Results appear in seconds.

🔒 100% Private

Your file never leaves your device. All processing happens client-side using pdf-lib. Zero data collection.

📑 Complete KDP Checks

Page count, dimensions, bleed, parity, margins, spine width, file size — all verified against official KDP specs.

📖 Built for Self-Publishers

Designed specifically for Amazon KDP paperback interiors. Avoid rejection and costly reprints by checking before you submit.

KDP Preflight Checker — Verify Your Book Before Publishing

Publishing a book on Amazon KDP requires your PDF interior to meet strict printing specifications. Page dimensions must match your chosen trim size (with or without bleed), page count must fall between 24 and 828 pages, and the file must be under 650 MB. Getting any of these wrong can lead to rejection or print quality issues.

Our free KDP Preflight Checker parses your PDF right in your browser using pdf-lib. It checks page count, verifies dimensions against your chosen trim size and bleed settings, ensures all pages are consistently sized, validates page count parity for duplex printing, calculates your spine width, and confirms file size limits. You get a clear pass/warn/fail report instantly.

No account required, no file uploads to servers, and no limits on usage. Just drag your PDF, pick your specs, and check.

What page counts does Amazon KDP accept?: KDP paperback interiors must have between 24 and 828 pages. Our checker flags your file if it falls outside this range.
What are the bleed dimensions for KDP?: If you enable bleed, KDP requires 0.125 inches on each side. That means your PDF pages should be 0.25 inches wider and 0.25 inches taller than the trim size.
Does this tool upload my PDF anywhere?: No. Your PDF is read entirely in your browser using JavaScript (pdf-lib). It never leaves your device. No server, no cloud, no storage.
What trim sizes does KDP support?: KDP supports several standard trim sizes including 5×8, 5.5×8.5, 6×9, 7×10, 8×10, and 8.5×11 inches, plus international sizes like A5 (148×210 mm). Our tool checks against all of these.
Why does page count parity matter?: Print books are printed on sheets with two sides. If your page count is odd, KDP will automatically add a blank page at the end. This is usually fine, but it's good to be aware of.
How is spine width calculated?: Spine width depends on the number of pages and paper type. For white paper it's approximately pages × 0.002252 inches, and for cream paper it's pages × 0.0025 inches.
Is this tool free?: Yes, 100% free with no limits. No account, no credits, no watermarks. Use it as often as you need.

KDP Preflight Checker