PDF Preflight
Upload a PDF. Find the problems that will get it rejected by a printer, an academic portal, or Amazon KDP โ before you send it.
Every check is PASS, WARNING, FAIL, or INFO. We never mark “couldn’t test” as a pass.
Print, KDP, academic, digital and general profiles apply different, source-grounded thresholds.
Where a check fails, we tell you exactly what to change before re-exporting.
Export a JSON or text preflight report you can archive or send to a colleague.
Drop your PDF here
or choose a file from your device
What are you preparing this for?
Each profile applies a different rule set. Unsupported checks are reported as INFO, not passed.
Opening PDFโฆ
Local processing only. No data is uploaded.
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๐ Need to check multiple files or get a readiness certificate?
Autonom Pro adds batch checking, software-specific fix guides, and a downloadable certificate you can attach to submissions.
Technical details
Why preflight a PDF before you submit it?
Most PDFs that get rejected are not broken โ they are unfit for a specific destination. A layout that looks perfect on screen can fail commercial print because fonts were not embedded, colors are RGB instead of CMYK, or the file has no BleedBox. A paper submission can be rejected because page sizes differ across the document. A KDP paperback can be refused because interior margins fall below Amazon’s current minimum for the page count.
Preflight is the practice of catching those failures before the file leaves your machine. Autonom PDF Preflight inspects your PDF locally in the browser, applying the rule set that matches what you are preparing it for.
What Autonom PDF Preflight checks
Document & metadata
PDF version, encryption, file size, linearization, title, author, subject, keywords, creator, producer, dates, language, and XMP presence.
Pages & geometry
Page count, page-size consistency, orientation consistency, non-zero rotation, blank-page detection, CropBox, BleedBox and TrimBox presence.
Fonts
Referenced fonts, embedding heuristic from font-file streams, and subsetting tags. Non-embedded fonts are the #1 cause of print rejection.
Images
Count of image XObjects across the document, with an honest INFO note where effective DPI is not measured by this version.
Color & transparency
RGB / CMYK / Gray operator detection, plus a graphics-state signal for possible transparency that offset printers may need flattened.
Structure & accessibility
Tagged PDF / MarkInfo, structure tree, outline, annotations, and interactive form fields.
Purpose-specific rulesets
- General โ core PDF health plus scanned/image-only document detection with an OCR suggestion.
- Print โ BleedBox and TrimBox presence, font embedding, CMYK expectation, and a 300 DPI requirement note.
- KDP โ trim-size check, interior margin note, font embedding, and minimum page count.
- Academic โ common journal file-size caps, font embedding, and tagging recommendation.
- Digital โ Fast Web View (linearization) and file-size note for email and browser delivery.
How to run a preflight in 3 steps
- Upload the PDF โ drag it onto the drop zone or choose a file from your device. Nothing is uploaded to a server.
- Choose the destination โ pick the profile that matches where the file is going: Print, KDP, Academic, Digital, or General.
- Review the report โ pass, warn, fail, and info results are grouped by category, with a fix suggestion wherever one applies. Download the report as JSON or text for your records.
Frequently Asked Questions
Is my PDF uploaded to any server?
No. Autonom PDF Preflight runs entirely in your browser. The PDF bytes are parsed by PDF.js locally, and no content, filename, or metadata is ever transmitted.
Why do some checks say INFO instead of PASS?
Because some things cannot be reliably determined by a browser without additional measurement. Effective image DPI, for example, requires per-image transform matrices we do not yet extract. Rather than falsely pass a check we cannot perform, we mark it INFO with an explanation. This is a deliberate design decision โ a passed check should mean something.
Does a warning mean my PDF will be rejected?
Not necessarily. A warning is a flag for something a human should confirm โ mixed orientations, an unembedded font, RGB-only color in a print profile. Many warnings can be ignored if you know the destination tolerates them. Fails are stronger: a supported rule was checked and did not pass.
Can I check a password-protected PDF?
Not fully. Autonom detects encryption and reports it as a warning, but the interior of an encrypted PDF cannot be inspected without the password. Remove encryption before preflighting if the recipient does not need it.
Do you support PDF/A or PDF/X validation?
Not yet. Conformance to those ISO standards requires both a rule set and a validation profile. This is on the roadmap. In the meantime, the report will not claim PDF/A or PDF/X compliance you cannot verify.
Can I use the report as evidence of compliance?
No. The report describes what Autonom PDF Preflight measured. It is intended as a preflight aid, not a substitute for a printer’s, publisher’s, or institution’s own validation toolchain.