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OS Authority

Repair a damaged PDF

When a PDF won't open, opens blank or shows an error, its internal index is often broken while the pages are still there. This tool rebuilds the file on your device and tells you honestly whether it found anything to fix.

Your PDF is processed on this device and never uploaded. We don't see, store or log your files.

How it works

  1. Tap Choose file and pick the damaged PDF.
  2. Tap Repair PDF.
  3. Read the result: repaired, or no damage found.
  4. Download or share the rebuilt file, and open it to check the pages.

Why repair here

Your PDF never leaves your phone or computer, which matters for contracts, statements and IDs. It is free, with no watermark and no sign-up.

What can be repaired

Every PDF ends with a table of where each object (page, font, image) starts in the file. A download that stopped early, a file copied from a failing USB stick or an email attachment that was cut off usually leaves that table missing or pointing to the wrong places, and many apps then refuse to open the file. The repair reads every object in order without trusting that table, rebuilds it, and saves a clean copy. Pages whose data is still in the file come back as they were.

What can't be repaired

Data that is not in the file can't be recovered: if a 10 MB PDF arrived as 4 MB, the pages stored in the missing 6 MB are gone, and the rebuilt file has only the pages that survived. Files that are not really PDFs (for example a web page saved with a .pdf name) and files overwritten with zeros can't be repaired either; the tool says so instead of giving you a broken copy. Password-protected PDFs must be unlocked first with the password.

Frequently asked questions

The result says no damage was found, but my PDF still won't open. Why?

The file's structure is fine, so the problem is likely the app: try another PDF reader or update it. Also try the rebuilt copy, which is written fresh and sometimes opens where the original didn't.

Will the repaired PDF look the same?

Yes for every page that could be read: text, images and fonts are copied, not re-created. Pages that were missing from the damaged file can't be brought back.

Can it repair a password-protected PDF?

Only after it is unlocked. If you know the password, remove it with Unlock PDF, then repair the unlocked copy.

Is my PDF uploaded?

No. Everything happens in your browser on your own device.

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