004 / PDF OPTIMIZATION TOOLS
100% Local • Zero ServersReduce file size or repair the integrity of your PDF file:
Compress PDF
Reduce file size while optimizing for maximal PDF quality.
Repair PDF
Upload a corrupt PDF and we will try to fix and recover it.
Unlock PDF
Remove PDF password security and permissions restrictions with vector engine.
Protect PDF
Encrypt your PDF with a password to keep sensitive data confidential.
Redact PDF
Remove sensitive content and text from PDF documents.
Compare PDF
Compare two document versions with linear-space Myers Diff, interactive curtain slider and SHA-256 audit trail.
How local file processing works
Learn about the workflow, practical tips, data protection, and frequently asked questions.
1. How to optimize, protect, and repair PDF files step by step
Select desired tool or upload your PDF document.
The engine parses data streams and internal PDF structure.
Apply compression, encryption password, or redaction of sensitive data.
Download your optimized and secured file immediately.
2. Limitations & useful tips
WHAT YOU CAN DO
RECOMMENDED TIPS
3. What happens to your document when optimizing it?
Your files are compressed, repaired, encrypted, or redacted exclusively in your browser. Zero bytes leave your device.
Key and redaction operations hide sensitive data or protect documents with zero intermediaries.
Upon completion, browser RAM automatically purges all buffers and the file is ready immediately.
4. Frequently Asked Questions
Q: How does compression work without sending the file to a server?
A local WebAssembly engine runs in your browser, rewriting and optimizing compression streams and graphics directly.
Q: Is text redaction truly permanent and irreversible?
Yes. Redacted content is destroyed at the vector level inside the PDF, preventing any extraction or copying.
Q: What encryption level is applied when password-protecting a PDF?
Standard 128-bit or 256-bit AES encryption is applied, universally compatible with Adobe Acrobat and all standard PDF readers.
Q: What types of errors can the PDF repair tool fix?
It rebuilds corrupted cross-reference (XREF) tables, recovers truncated page streams, and restores damaged document indices.
Q: How does comparison between two PDF files work?
It visually analyzes and highlights additions, deletions, and textual or layout changes between two versions side by side.