Rebuild a damaged PDF by copying its pages into a fresh document. This tool uses pdf-lib to re-parse and re-serialize each page, recovering from common corruption issues — entirely client-side. Your file never leaves your device.
Key Features of Repair PDF
- Page-by-Page Reconstruction Traverses corrupted dictionary references, isolating and migrating readable page nodes into a fresh structure.
- Automatic Damage Skipping Gracefully skips unreadable elements and truncated pages to salvage the rest of the file instead of failing completely.
- Rebuilds Document Trees Heals broken reference tables and cross-reference indices (XREFs) that cause reader software crashes.
- Completely Private Repair Operations run entirely inside your browser's execution memory; no file data is sent over the internet.
Repair PDF Examples
Salvaging a Truncated Report
Attempt to restore a partially downloaded corporate PDF that crashes when opened.
Input
IncompleteReport_Corrupt.pdfOutput
IncompleteReport_Recovered_Pages.pdfHow to Use Repair PDF
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1. Upload the Broken PDF
Drag and drop the corrupted or damaged PDF file onto the drop zone or click to browse and select it.
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2. Attempt Repair
Click 'Repair PDF & Download'. The tool will try to load and rebuild the document page by page using pdf-lib.
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3. Download the Repaired File
If repair succeeds, the tool will download a rebuilt PDF. Pages that could not be recovered are skipped.
Common Use Cases for Repair PDF
- Recovering Incomplete Downloads Salvage partially written PDFs resulting from network drops or server timeouts.
- Healing Flash Drive Corruptions Restore documents with damaged headers from corrupted flash disks or external cards.
- Fixing Bad Scans Clean up and rebuild PDFs that have incomplete or corrupted data from faulty scanner drivers.
The Technical Details
The Repair PDF utility uses pdf-lib to bypass standard document header constraints. Rather than attempting to load the entire document tree as a single valid reference (which fails if the file is corrupt), the tool initializes a clean, fresh PDF frame.
It then runs a scanning sequence on the binary ArrayBuffer, parsing the dictionary streams byte-by-byte to find valid /Page tags. Accessible pages are copied individually into the new file, which automatically compiles fresh cross-reference tables (XREFs) on download.
Frequently Asked Questions
What types of damage can this tool fix?
It can recover PDFs with minor structural corruption, incomplete writes, or truncated data. Severely corrupted files where core structure is lost may not be recoverable.
What happens if a page cannot be recovered?
The tool skips unrecoverable pages and includes only the pages it can successfully read. The download contains whatever content was retrievable.
My repaired PDF is missing content — why?
If the original file was heavily corrupted, some data may be permanently lost. The tool reconstructs what it can from the remaining valid data.
Is my file sent to a server for repair?
No. The repair process runs entirely in your browser using pdf-lib. Your file is never uploaded or stored anywhere.