Repair Corrupted PDF
Fix damaged PDF files that won't open or display errors. Repairs invalid objects, corrupted structure, and bloated xref tables — all in your browser.
How to Repair a Corrupted PDF
Upload Your Damaged PDF
Drop the corrupted PDF onto the upload area. The repair tool will attempt to parse it using pdf-lib's lenient reader — no server needed.
Automatic Repair
The tool tries up to three levels of repair: strict parse → lenient parse (ignores invalid objects) → remove encryption wrapper. It reports exactly what was fixed.
Download Clean PDF
Download the repaired PDF with a clean, optimised structure. Redundant data is stripped during the re-save, often resulting in a smaller file.
Frequently Asked Questions
What types of PDF corruption can this tool fix?
The tool can recover PDFs with corrupted or duplicated object streams, invalid cross-reference (xref) tables, malformed page tree structures, and owner-locked encryption wrappers. It cannot recover PDFs where the page content streams themselves are destroyed (e.g., partially overwritten files).
Why won't my PDF open — what usually causes corruption?
The most common causes are incomplete downloads (file cut off mid-transfer), failed save operations (power loss or crash during save), email attachment corruption, storage media errors, or partially failed PDF generation from software. This tool addresses all of these except physical media errors.
Does the repaired PDF keep all pages and content?
In most cases, yes. Content that is stored in valid page streams is preserved exactly. If an object is unrecoverable, it is removed cleanly rather than causing the entire document to fail.
My PDF says "file is damaged" but it still opens — should I repair it?
Yes. A PDF that opens with a warning has a structural issue that may cause problems in stricter PDF viewers (e.g., for legal submission or printing). Running it through the repair tool produces a clean, standards-compliant file.
Can this tool fix a PDF that was encrypted or password-protected?
If the PDF has an owner restriction (permissions lock) but no open password, the repair tool can strip it. If the PDF requires an open password to view, use the Unlock PDF tool first (you will need the correct password), then repair.
Is there a file size limit for repair?
No hard limit. Processing happens entirely in your browser, so the only constraint is your device's available RAM. Files up to 200 MB should work on modern hardware.
Is my PDF sent to a server?
No. The entire repair process runs locally using pdf-lib (WebAssembly) in your browser. Your file is never uploaded to PDFForge or any third party.