Why does KDP say it cannot convert my file?

The usual structural culprits: password protection, mixed page sizes, a size that matches neither the trim nor the trim-plus-bleed dimensions, or a file over the 650 MB limit. This checker tests each of those locally before you upload.

Can a PDF look correct but still have low-resolution images?

Yes — viewers upscale smoothly, so a 100 DPI page looks fine on screen. This MVP checks structure (sizes, fonts, security, counts); check individual page images with the 300 DPI checker, and treat KDP's previewer warnings as the final word on resolution.

Do fonts need to be embedded?

Yes. KDP requires all fonts embedded in interior PDFs; text set in a non-embedded font can be substituted or rejected. Coloring books with image-only pages typically have no fonts at all — which also passes.

Does this checker guarantee approval?

No. It catches common structural failures before upload, but KDP's own review covers content, margins and print factors this tool does not judge. A clean report is a good sign, not an approval.

KDP Coloring Book PDF Preflight Checker

Check your interior PDF against your trim and bleed choice before uploading — size uniformity, dimensions, fonts, security and page count, all parsed locally.

Trim size

Bleed setting you chose in KDP

Bleed (PDF) No bleed

Check your interior PDF (parsed on your device)

The PDF is parsed entirely in your browser and never uploaded. Set trim and bleed above first.

Select the trim size and bleed setting you used in KDP, then load the PDF. You get a page-numbered pass / warning / review report on file size, encryption, page count, size uniformity, expected dimensions and font embedding.

Structural checks only — image resolution inside the PDF, margin-safety of artwork and content policy are outside this MVP. A clean report is never a "KDP approved" claim. Files are parsed in the browser and are not uploaded, stored or logged.

Data source: spec version kdp-spec-2026-08, last verified against the official KDP help pages on 2026-08-25.

KDP can change its specifications at any time — always confirm against the official pages before uploading. This tool gives print-spec math only; it does not guarantee KDP acceptance. All calculations run in your browser and nothing you enter is uploaded or stored.

What the kdp coloring book pdf checker verifies

File size — against KDP's 650 MB manuscript limit.
Security — password-protected PDFs cannot be processed by KDP.
Page count — against the official range for your trim (24 up to 590–828).
Uniform page size — every page must share one size; outliers are listed by page number.
Expected dimensions — detected size vs trim ± bleed, including the classic "bleed selected but trim-size PDF" mismatch.
Font embedding — non-embedded fonts are named; image-only interiors pass automatically.

Worked example

You selected 8.5" × 11" with bleed in KDP, but the checker detects every page at 8.5" × 11" exactly. That is the classic mismatch: a bleed book must be 8.625" × 11.25". The report says so explicitly — fix it by re-exporting at the bleed size (or switching KDP to no-bleed), not by guessing which side to change.

Common mistakes

Uploading first, checking after rejection. Each failed review costs days; structural issues are catchable in seconds locally.
One rogue page size. A cover page pasted into the interior, or one page exported from a different tool, breaks size uniformity.
Password-protected exports. Some design tools add security by default.
Trusting screen preview for resolution. Check page images separately with the 300 DPI checker.

Frequently asked questions

Why does KDP say it cannot convert my file?: The usual structural culprits: password protection, mixed page sizes, a size that matches neither the trim nor the trim-plus-bleed dimensions, or a file over the 650 MB limit. This checker tests each of those locally before you upload.
Can a PDF look correct but still have low-resolution images?: Yes — viewers upscale smoothly, so a 100 DPI page looks fine on screen. This MVP checks structure (sizes, fonts, security, counts); check individual page images with the 300 DPI checker, and treat KDP's previewer warnings as the final word on resolution.
Do fonts need to be embedded?: Yes. KDP requires all fonts embedded in interior PDFs; text set in a non-embedded font can be substituted or rejected. Coloring books with image-only pages typically have no fonts at all — which also passes.
Does this checker guarantee approval?: No. It catches common structural failures before upload, but KDP's own review covers content, margins and print factors this tool does not judge. A clean report is a good sign, not an approval.