About repairing PDFs
A PDF is a collection of numbered objects, with an index at the end of the file, called the cross-reference table, that says where each object starts. When a download is interrupted, a file is copied or emailed badly, or a program saves it with mistakes, that index or the length of a data stream can be wrong, and readers then refuse the file, show blank pages or warn that it is damaged. This tool opens the file with the recovery built into qpdf, which finds every object by scanning the file itself, corrects stream lengths and replaces objects that cannot be read. Every page is then checked and the whole document is written again with a fresh, correct index, compressed and linearised for fast web view, so it opens quickly in browsers. Nothing is changed in how pages look. A repair can only bring back what is still in the file: if part of it is missing, for example because a download stopped halfway, the lost pages cannot be recreated, and a file that is not really a PDF cannot be repaired at all. In that case, download or ask for the file again. A file that needs a password must be unlocked first with Unlock PDF.
Limits: files up to 25 MB with a free account, 200 MB on Pro and 500 MB on Business; up to 3 files per task on Free, 50 on Pro and 200 on Business, with up to 2,000 pages each. A free account includes 10 server tasks a day.
Before you sign in, files can be up to 25 MB and you can run 10 server tasks a day. A free account raises this to 25 MB and 10 tasks a day.
Privacy: your file is uploaded over an encrypted connection to our UK servers, processed automatically with no person opening it, and deleted within 2 hours (1 hour on Free), or straight away with Delete now.
How to use the PDF tools: Step-by-step help with every tool, limits and your files.
Repair PDF: frequently asked questions
Which problems can this fix?
A broken or missing cross-reference table, wrong stream lengths, damaged objects and other structural mistakes, which cause most "file is damaged" errors.
Why does it say the file could not be repaired?
The file has too little of the original PDF left, or is not a PDF at all. Download or ask for the file again; a repair cannot recreate missing pages.
My PDF was fine. Is it still useful to run it?
Yes. A healthy file is rewritten with a clean structure and linearised for fast web view; the result page says no damage was found.
Will the repair change my pages?
No. Pages, text, images and links stay the same. Only the file's internal structure is rebuilt.
Can it repair password-protected PDFs?
If the PDF needs a password to open, unlock it first with Unlock PDF. Files that only restrict printing or copying are repaired and keep their restrictions.