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Repair PDF · compare engines
Rebuild the same damaged PDF with QPDF and with PDFium side by side, then compare pages, text and size of both copies. Files stay in your browser.
Engines:QPDFPDFiumCompare engines
The next tool opens in a new tab. Keep this tab open until the file arrives. The PDF is passed locally; it is not uploaded or saved in browser storage.
QPDF
Used by Repair PDF on the PDF sites. Reconstructs the cross-reference table while reading and writes a new, checked file.
Not run
Download QPDF copyPDFium
Opens the file with PDFium's own recovery and saves a new copy with FPDF_SaveAsCopy.
Not run
Download PDFium copyWas this tool useful?
Try an example
Download sample PDFThe sample has a broken cross-reference table. Both copies should open with two pages and Total: 148.50; file sizes differ because each engine writes the file its own way.
What to expect
Both copies are read back by PDFium to count pages and extractable characters, so the numbers are comparable. More pages or text is not always better: check every page of the copy you keep. Content that is missing or overwritten in the damaged file cannot be restored by either engine.
Password-protected PDFs must be unlocked first. Rewriting a PDF can invalidate digital signatures.