Drop a PDF that will not open or shows errors – the repair starts by itself, and you see how many pages were recovered.
The repair starts by itself – no options to set.
The cross-reference table and page tree are rebuilt and every page is checked.
The result says how many pages were recovered, e.g. “Recovered 12 of 14 pages”.

Share any size of PDF, video or Office file as a HelpRange link: it opens instantly in the browser, you get an alert when it is read and can revoke access later.
A PDF breaks most often when a download or an upload is interrupted, when a program crashes while saving, or when a file is copied from a failing disk or e-mail system. The pages are usually still in the file – what is broken is the index that tells a viewer where they are. Rebuilding that index brings the document back.
A PDF ends with an index (the cross-reference table) that tells a viewer where every page and picture starts. When a download stops early, an e-mail system cuts an attachment, a program crashes while saving or a file is copied from a failing disk, that index is the first thing to go – and viewers report the file as damaged although most pages are still inside. The repair reads the file from the start, finds the pages and writes a new, clean file around them.
Pages whose content is missing from the file cannot be recreated. Ask the sender for the file again, download it once more, or look for an older copy – and check a fresh copy with the PDF security check before you open a file from an unknown source. A PDF that asks for a password is not damaged; this tool does not remove passwords.
Broken or missing cross-reference tables, junk before the start of the file, a damaged page tree, files cut off during a download or an e-mail transfer, and single pages that cannot be read (they are left out or kept as images).
Often, but not always. Pages whose content is missing from the file cannot be brought back – the result tells you exactly how many pages were recovered, e.g. “Recovered 12 of 14 pages”.
No. A PDF that asks for a password is not damaged – this tool does not remove passwords.
Only for a short time: uploads are deleted right after processing, the result after 30 minutes – or at once with “Delete now”.
The repair writes a new file with only the pages and their content; it does not check for malicious content. For a file from an unknown sender, run the PDF security check too.