Repair a PDF
A file that no longer opens goes in, a readable document comes out.
Your files never leave your deviceDrop your damaged PDF here
A truncated file, one that closed incorrectly, or one your usual reader refuses to open
How to repair a damaged PDF, step by step
A truncated file, one closed incorrectly by a printer, or one your usual reader refuses goes through two rebuilding engines before VellumPDF gives up.
Drop in the damaged PDF
VellumPDF does not read it beforehand: it hands it over as-is to the repair engine, precisely so it does not fail where that engine can still work.
Click “Repair”
The first engine, qpdf, rebuilds the cross-reference table and reassembles the file’s objects.
Let the second engine take over if needed
If qpdf fails, VellumPDF automatically tries to rebuild the document from whatever objects are still readable. A message states this and suggests checking the result before sharing it.
Download the repaired file, or try again
If both engines fail, the detailed error message is shown and a button lets you try a different file.
The two engines fail on different edge cases; neither can recreate data that is truly gone. Repair also strips the file’s printing and copying restrictions along the way, but never an opening password.
Frequently asked questions
How does VellumPDF repair a corrupted PDF that no longer opens?
It analyzes the file and rebuilds its internal cross-reference table — the structure a PDF reader uses to locate pages and objects — to produce a valid file again. Recoverable content, text and images, is preserved as far as possible.
Can the repair recover data that is genuinely lost?
No. Some PDFs are damaged beyond any automatic repair: if the missing data is truly destroyed, no tool, including VellumPDF, can invent it from nothing.
Is the damaged file sent to a server to be repaired?
No, the repair happens entirely in your browser, without sending the document to a server, and the service is free.
Is there a second repair engine if qpdf fails?
Yes. If qpdf gives up — for instance because the cross-reference table is entirely missing — VellumPDF retries with the pdf-lib engine, which can rebuild a document from the objects that are still readable even without that table. The two engines fail on different kinds of damage; chaining them recovers files that neither would save alone. The result from this second engine is flagged, so you can check it before sharing it.
What does the “minor issues” warning after a repair mean?
It corresponds to qpdf’s exit code 3, which signals success along with a few warnings — minor inconsistencies corrected automatically along the way, without the repair having failed. The downloaded file is complete; the warning is informational, not a sign of partial failure.
Does the repair also remove printing or copying restrictions from the PDF?
Yes, as a side effect. qpdf needs to rewrite the file completely to repair it, which a merely restricted document would otherwise refuse; VellumPDF therefore always strips such restrictions as part of the operation. It does not, however, remove an opening password: a PDF that requires one still asks for it after repair.