How Repair PDF works

Repair PDF tries to rebuild a file that a reader refuses to open or that lost the last page in a bad save.

If the file is truncated or encrypted, repair cannot invent the missing bytes.

Steps

1. Drop the damaged PDF.
2. Run repair and download the new file.
3. Open it and check the page count.
4. If it still fails, the source file may be incomplete.

Limits

Repair is a best effort on readable structure. It will not decrypt a password you do not know.

What repair actually retries

The tool opens the PDF and copies the pages into a new file. If that open fails, it falls back to pictures of the pages, the same idea as a strong compress.

A file the browser cannot parse at all will not come back as the original text. Keep any older copy you still have.