How to repair a PDF
- Select the damaged PDF or drop it onto the page.
- Click repair. The file is scanned and rebuilt by the qpdf engine in your browser.
- Read the result: it shows whether the file was rebuilt and any warnings found along the way.
- Download the repaired copy and open it to check the content.
What can be repaired
A PDF contains a cross-reference table, an index telling readers where every part of the file is stored. Interrupted saves, faulty export tools, email systems and transfer errors frequently break this index, and readers then refuse to open the file or show blank pages. The repair process ignores the broken index, scans the file to find every object, and writes a clean, consistent copy. This fixes a large share of "file is damaged" errors.
What can't be repaired
Repair can only work with data that is still in the file. If a download stopped halfway, the missing pages simply don't exist and cannot be recreated. Files that were overwritten, encrypted with an unknown password, or are not really PDFs (for example a renamed Word document) cannot be fixed here. We say so honestly rather than producing an empty file.
Tips
- Try downloading the original again first; a fresh copy is often intact.
- Keep the damaged original until you have checked the repaired copy, and look through every page.
- After repair, Optimize PDF can tidy the file further.
- If the file opens but other tools on this site report errors, repairing it first often solves the problem.
Repair runs locally in your browser, so the file is never uploaded.
Frequently asked questions
Can every corrupted PDF be repaired?
No. Structural damage such as a broken index can usually be fixed, but content that is missing from the file, for example after an incomplete download, cannot be recovered.
Will repair change my document's content?
No. It rebuilds the file structure and keeps the content it can find.
My PDF is password protected. Can repair remove the password?
No. Repair does not bypass passwords. If you know the password, use Unlock PDF.
Is my file uploaded?
No. The repair engine runs in your browser.