What kind of repair is this?

It rewrites readable pages into a fresh PDF structure. It is conservative repair, not deep forensic recovery.

What if the file cannot be opened?

If the browser cannot read any pages, a desktop repair app or server-side repair engine may be required.

No. Repair runs locally in your browser.

Repair PDF

Rewrite readable pages into a fresh PDF structure. Deeply corrupted files may need desktop repair software.

Enable JavaScript to use this browser-based PDF tool. The live app runs file processing locally in your browser when the tool supports local processing.

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