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Repair PDF

Re-parse PDFs with broader tolerance — recovers files that strict parsers reject

This workflow reads the selected file from browser memory and creates the download locally. AntiUpload, analytics, and ads receive neither the file nor its working buffers.

  • No file upload
  • Runs on your device
  • Ads cannot access files
  • No account

Drop your PDF files here

or

Up to 200MB on this device — processed in RAM, never uploaded

100% Local Processing
Zero Server Uploads

About Repair PDF

Repair PDF keeps the complete file workflow inside this browser tab. Your selected file, its name, contents, settings, and generated output are not sent to AntiUpload or a cloud conversion service. Ads and aggregate traffic analytics stay outside the processing boundary and receive no file object or working buffer.

Repair PDF re-parses your file with progressively broader tolerance — accepting malformed indirect objects, ignoring corrupted /Info dicts, and copying pages one at a time when bulk-load fails. Whatever pages still parse get re-saved into a fresh PDF whose structure is rebuilt from scratch by pdf-lib's writer.

Honest scope: this isn't a full byte-scan recovery tool like desktop Acrobat or qpdf. It can't reconstruct a missing cross-reference table from raw bytes, and it can't rescue files that are truncated mid-stream. What it CAN do: fix files that strict parsers reject due to spec-bending exports, recover the surviving pages of a partially-broken PDF, and strip out invalid metadata that trips other readers.

If the first few strategies fail, a fallback uses pdf.js (a different, more tolerant parser) to render and re-emit each page — this rescues many files that pdf-lib alone can't open. When that also fails, the file is genuinely beyond what browser-based tools can fix; try desktop Acrobat's repair mode or qpdf.

How it works

  1. Upload your problematic PDFEven if other PDF viewers refuse to open it, this tool tries multiple parsing strategies before giving up.
  2. Click RepairThe tool tries strict parse → lenient parse → page-by-page recovery → pdf.js fallback. The first strategy that produces a readable document wins.
  3. Download the resultThe output is a fresh PDF written from whatever the parser could read. Open it in your normal viewer to check — if pages are missing or visuals look off, the source was beyond browser-tool recovery.

When to use Repair PDF

Files rejected by strict PDF parsers
Some PDF generators (especially older or non-Adobe ones) produce technically invalid PDFs that strict viewers reject. Re-parsing with looser tolerance often opens them.
PDFs with corrupted metadata
When a PDF's /Info dict has malformed values, some readers refuse to load the whole file. Skipping the metadata-update pass and re-saving usually fixes it.
Partially broken multi-page PDFs
If individual pages have broken object references but most of the document is intact, the page-by-page recovery mode salvages the working pages.

Frequently asked questions

Does Repair PDF upload or share my files?
No. Input files are read from browser memory and the output is created locally for your download. AntiUpload does not send file bytes, names, sizes, page counts, contents, passwords, or generated outputs through analytics or advertising requests.
Can it fix any broken PDF?
No — and we want to be honest about that. Files with truncated downloads (last bytes missing), totally corrupted cross-reference tables, or completely missing content streams are beyond what an in-browser tool can recover. For those, desktop Acrobat's 'Recover PDF' mode or the qpdf command-line tool are better options. What we CAN handle: files that strict parsers reject because of spec-bending exports, files with corrupted metadata, and files where most pages parse but a few have broken references.
Will I lose any content during repair?
Possibly — if individual pages can't be parsed, they're skipped and the success message tells you how many were recovered vs lost. The pages that survive come through intact (text is selectable, images are preserved). For partially-broken multi-page PDFs the typical outcome is 'most pages recover, a few are lost'.
Does it work on password-protected files?
No. Unlock first (with the password), then repair.
Is the repaired file smaller than the original?
Sometimes — re-saving via pdf-lib uses object streams, which often compresses better than the source. But if the source had aggressive compression already, the output may be slightly larger.
Why didn't this fix my file?
If all four strategies plus the pdf.js fallback fail, the file is genuinely too damaged for browser-based parsing. Try opening it in desktop Adobe Acrobat with File → Recover PDF, or run `qpdf --check` from the command line — both can do byte-level scans we can't.
Is it safe to repair a PDF here?
Yes. Your file is repaired entirely in your browser and is never uploaded to a server, so even a sensitive or confidential document stays on your device. After the page loads you can disconnect from the internet and the repair still works.
Can I repair multiple PDFs at once?
Yes, you can add several PDFs and repair them in one batch. Each file is processed locally in your browser, so nothing leaves your device no matter how many you add.
Does this work on Windows, Mac, and mobile?
Yes. It runs in any modern browser, so the same page works on Windows, Mac, iPhone, and Android with nothing to install.

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