Fix corrupted PDF files with diagnostic report — 3 repair modes, health score, and full transparency on what was fixed
WhiskFile Repair PDF is a free online tool to fix corrupted PDF files with diagnostic report — 3 repair modes, health score, and full transparency on what was fixed. Files are processed entirely in your browser — nothing is uploaded to any server.
Quick Answer
Fix corrupted PDF files with diagnostic report — 3 repair modes, health score, and full transparency on what was fixed. WhiskFile's Repair PDF is free, works in your browser, and requires no account. Your files never leave your device — all processing happens locally.
Upload your PDF
Drag and drop or click to select the corrupted PDF file you want to repair. There are no file size or page count limits.
Select your symptoms
Optionally choose the symptoms you're experiencing (won't open, error messages, missing pages, garbled text, truncated, slow loading) to get a recommended repair mode.
Choose a repair mode
Select Quick Fix (fast structural rebuild), Deep Repair (full Ghostscript rewrite), or Aggressive Recovery (GS rewrite + qpdf cleanup). The symptom selector auto-recommends the best mode.
Start the repair
Click Repair to begin. The tool runs qpdf diagnostics, applies the selected repair strategy, and runs diagnostics again to verify the fix.
Review the diagnostic report
Check the before/after diagnostic output and health score (0-100) to see exactly what issues were found and which were resolved.
Download the repaired PDF
Download your fixed PDF file. If the health score is low, try a more aggressive repair mode for better results.
Max file size: 50 MB (free) · 500 MB (paid). Processing time: ~15s on average. Upload one file at a time.
Repair PDF runs entirely in your browser — no software to install. Works on any device with a modern browser.
Windows & Mac
Chrome, Firefox, Edge, Safari
iPhone & Android
Safari, Chrome mobile
iPad & Tablets
Full touch support
Unlike server-based tools that upload your documents, WhiskFile processes everything locally in your browser. Your files never leave your device — not even temporarily.
No upload required
Files are processed in your browser — nothing is sent to any server
100% private
No server storage, no data collection, no third-party access
Works offline
Once loaded, works without an internet connection
“Compressed PDFs email in seconds instead of minutes. My clients love the fast turnaround.”
Tom Wilson
Real Estate Agent
“OCR on scanned papers makes them searchable instantly. A massive time-saver for literature reviews.”
Emily Zhang
Academic Researcher
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Client-side processing
This tool now runs entirely in your browser — files never leave your device.
Result preview & sharing
Preview your processed file before downloading, and share results via a secure link.
Not always. Quick Fix handles ~80% of corruption (broken xref tables, stream errors). Deep Repair recovers more by fully rewriting the file. Aggressive Recovery salvages the most, but severely damaged files with missing data may not be fully recoverable. The diagnostic report shows exactly what was fixed.
Quick Fix (qpdf) rebuilds the file structure — fast and handles most common issues. Deep Repair (Ghostscript) rewrites the entire PDF from scratch — slower but fixes deeper corruption. Aggressive Recovery uses Ghostscript with maximum error tolerance, then runs a qpdf cleanup pass — best for files that won't open at all.
The health score (0-100) compares structural issues before and after repair. 90-100 means the PDF is fully healthy, 60-89 means partial recovery with some warnings, and below 60 means significant issues remain. We run qpdf --check before and after repair to calculate this.
Common causes: incomplete downloads, interrupted saves, storage media errors, email attachment encoding issues, application crashes during PDF creation, file system corruption, or transferring between incompatible systems.
Most repair tools are black boxes — you upload a file and hope for the best. WhiskFile shows a full diagnostic report: health score, issues found and fixed, before/after comparison. You also get 3 repair modes instead of one-size-fits-all.
The symptom selector is a quick way to get started — it auto-selects the best mode based on your problem. For example, 'Won't open at all' selects Aggressive Recovery, while 'Loads very slowly' selects Quick Fix. You can always override the selection.
Yes. Files are transferred over TLS encryption, processed in an isolated environment, and automatically deleted within 1 hour. No human access, no AI training, no data sharing.
Try a more aggressive mode. If Quick Fix didn't work, try Deep Repair or Aggressive Recovery. The diagnostic report helps you understand what's wrong and whether the file can be recovered.
Select the symptoms you're experiencing — such as 'won't open,' 'missing pages,' or 'garbled text' — and the tool automatically recommends the best repair mode. For example, 'won't open' maps to Deep Repair, while 'garbled text' suggests Aggressive Recovery.
The diagnostic report shows the full qpdf --check output before and after repair. It lists every structural issue found in your PDF (invalid cross-references, missing objects, stream errors) and confirms which issues were resolved by the repair.
Yes. Incomplete downloads are one of the most common causes of PDF corruption. Quick Fix can often rebuild the structure, but if the file is severely truncated, Deep Repair or Aggressive Recovery may be needed.
Blank pages usually indicate corrupted page content streams or missing font/image resources. Deep Repair rewrites the entire document through Ghostscript, which can recover readable content from damaged streams.
Yes. Repair PDF is completely free with no signup, no task limits, and no watermarks. There are no file size or page count restrictions.
Yes. Repair PDF works on any device with a modern browser — iPhone, Android, iPad, tablets, Chromebooks, and desktop computers. No app download required. The interface adapts to your screen size automatically.
Repair PDF accepts PDF files as input and produces PDF output. The maximum file size is 50 MB on the free plan (500 MB for Pro users). There are no page count limits.
See how WhiskFile compares to other PDF tools on features, pricing, and privacy.
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