Repair Corrupted PDF Free Online – PDF Repair Tool
Repair PDF
Fix corrupted or damaged PDFs by re-serializing and rebuilding internal structure
Drop a PDF here
Upload a PDF to attempt repair
Max file size: 100MB
100% Private: All processing happens in your browser. Your files never leave your device.
Repair PDF re-parses an uploaded file with pdf-lib, copies every page it can successfully read into a fresh PDF document, and lets you download that rebuilt copy. It tries a normal load first; if that throws, it retries once with a more lenient loading mode before giving up. This is aimed at PDFs whose internal structure (a broken cross-reference table, a malformed object) confuses a stricter viewer even though the actual page content is intact — the kind of file that a scanner app or an older tool produced and that won't open somewhere else, not a file with genuinely missing or damaged data.
Two things are worth knowing before you rely on this. First, the “Actions Taken” list you see afterward (“Re-serialized all page objects,” “Rebuilt cross-reference table,” “Validated page tree structure”) is fixed confirmation text that appears every time a repair completes successfully, not a diagnostic record of what was specifically wrong with your file — it shows up even for a PDF that had nothing wrong with it. Second, a repaired PDF always gets its Producer field overwritten to “TryDocsy PDF Repair,” regardless of what produced the original.
How it works
1. Drop a PDF here
One file, up to 100 MB.
2. Press Repair PDF
pdf-lib attempts a normal load. Only if that fails does it retry in a more lenient mode; if both attempts fail, the file is reported as unrecoverable and no repair is attempted further.
3. Read the report
A card shows Repair Complete or Repair Failed, the page count and any title/author found, then two lists: Issues Found and Actions Taken.
4. Download Repaired PDF
Only appears if repair succeeded. The filename gets “-repaired” appended — but only when the original name ends in a lowercase .pdf, since the renamer looks for that exact text.
When you'd use it
A PDF that won't open elsewhere
A file exported by an older tool or a budget scanning app sometimes shows a generic “invalid” or “damaged file” error in one viewer while looking otherwise complete — re-serializing it with pdf-lib can produce a copy that opens normally.
A file a colleague says won't open on their device
Before resending a PDF that someone reports as broken, running it through repair rebuilds its internal structure in case the original export left something malformed, without you needing to know what specifically was wrong.
Cleaning up a PDF's structure before another tool
Some downstream tools are pickier about well-formed PDF structure than the viewer you used to check the file. Repairing first gives you a freshly rebuilt cross-reference table and page tree to hand off instead.
A downloaded PDF that half-loads in a browser tab
A file that shows a few pages then stalls or errors in an in-browser PDF preview, but downloads at the expected file size, is a plausible candidate for a structural fix rather than genuine data loss.
What “repair” actually does here
There's no byte-level forensic recovery happening. The tool leans entirely on whatever pdf-lib's own parser can make sense of: if it can load the file (on the first try or the lenient retry), every page it finds gets copied into a new PDFDocument and saved fresh, which is often enough to fix a broken cross-reference table or corrupted trailer that a stricter viewer refuses to open. If pdf-lib can't parse the file at all on either attempt, the tool reports it as severely corrupted and offers no download — there's no further attempt to guess at the missing structure.
What it can't fix
An encrypted PDF isn't repaired — if the file loads with zero readable pages, the tool reports “This PDF is encrypted or has no readable pages — unlock it first” and stops, pointing you at a separate unlock step rather than attempting anything. And repair can only rebuild structure around content pdf-lib can actually read; if the underlying image or font data inside a page is itself damaged rather than just poorly organized, that damage travels into the repaired copy along with everything else.
What changes in your PDF's metadata
Every successful repair sets the Producer field to “TryDocsy PDF Repair,” overwriting whatever software originally produced the file. Title and Author are carried over only if the original PDF had them; if both are missing, the report flags “Missing metadata (title, author)” as an issue, but the tool doesn't fill them in for you — it's a note, not an automatic fix.
Frequently asked questions
Can this tool unlock a password-protected PDF?
No. If a PDF loads with zero readable pages, the tool reports it as encrypted and tells you to unlock it first — it does not attempt to remove or guess a password.
What does the 'Actions Taken' list actually tell me?
It's fixed confirmation text — the same three lines appear on every successful repair, whether or not your file had a real problem. It's not a log of what was specifically fixed in your PDF.
Will repairing change my PDF's metadata?
Yes, in one specific way: the Producer field always becomes “TryDocsy PDF Repair,” even if nothing else needed fixing. Title and Author are kept only if the original file had them.
What happens if my PDF can't be repaired at all?
If pdf-lib fails to load it on both the normal and lenient attempts, the report says the PDF is severely corrupted and cannot be recovered, and no download is offered.
Why doesn't my downloaded file have “-repaired” in its name?
The renamer looks for a literal lowercase “.pdf” at the end of the filename. If your original file's extension is uppercase (like REPORT.PDF), that text isn't found, so the download keeps the original name unchanged — the content inside is still the repaired file.
Can this recover content that's actually missing or damaged inside the PDF, not just disorganized?
No. Repair rebuilds the file's structure around whatever pdf-lib can read; it can't reconstruct image or font data that's genuinely corrupted or absent, only reorganize what's still readable.