Repair PDF – Fix a Damaged or Corrupted PDF

A PDF that shows "file is damaged", opens blank or stops halfway usually has a broken index rather than lost content. Every PDF ends with a cross-reference table that tells readers where each object starts; an interrupted download, a bad email gateway or a failing disk can break that table even though the pages themselves are still in the file. This tool reads the objects one by one, rebuilds a clean structure and saves a fresh copy, without uploading anything.

How to use this tool

1. Drop the damaged PDF (or several).
2. Keep "Automatic": it first rebuilds the structure, which keeps text, fonts and quality, and only renders pages as images when that fails.
3. Press Calculate and read the report of what was wrong.
4. Download the repaired file and check it in your usual PDF reader.

Formula

Pass 1: read every "n 0 obj … endobj" in order → collect the page objects → copy them into a new PDF with a fresh cross-reference table. Pass 2 (if needed): render each readable page and rebuild it as an image.

Pass 1 ignores the old cross-reference offsets completely, so a wrong or missing table does not matter. If the page list itself is broken, pages are collected from the page objects in the order they appear in the file. Pass 2 uses a second, more forgiving PDF engine; pages rebuilt that way look the same but their text is no longer selectable.

Example

A 24-page report was cut off at 92% while downloading. The check reports "The end-of-file marker is missing" and "The cross-reference table is damaged". Pass 1 finds 22 complete page objects and copies them into a new file, so the repaired PDF opens with 22 pages of selectable text; the last two pages were never downloaded and cannot be recovered.