Compress PDF Without Uploading Files
Runs 100% in your browser. Your files never leave your device.
Use this tool nowMost online PDF compressors require you to upload your files to their servers. This means your sensitive documents travel across the internet and are stored on third-party systems — even if only temporarily. With JuTasks, compression happens entirely in your browser using WebAssembly technology. Your PDF never leaves your device, making it the safest choice for confidential documents like contracts, medical records, or financial statements.
Why use JuTasks for this?
No file uploads
Your files are processed entirely in your browser. Nothing is sent to any server.
No account required
Start using immediately. No sign-up, no email, no tracking.
Instant processing
No waiting for uploads or downloads. Results appear instantly.
Works offline after load
Once the page loads, you can work without an internet connection.
Ideal for sensitive documents
Perfect for legal, health, financial, or any confidential files that should never leave your device.
Ready to get started?
PDF Compressor is ready to use right now. No installation, no sign-up required.
Use this tool nowHow it works
How does this tool work locally?
When you drop a PDF into JuTasks, our compression engine runs directly in your browser using modern JavaScript and WebAssembly. The file is processed locally on your device, and the compressed result is generated without any network requests. You download the result directly from your browser's memory.
Why is local processing more secure?
Traditional online tools upload your files to remote servers where they're processed and stored. Even with 'delete after processing' promises, your data has already traversed the internet and touched third-party systems. With browser-based processing, your file never leaves your device — there's no server to trust, no data in transit, and no copies stored anywhere.
When should you use this tool?
- Compressing confidential business documents
- Reducing file size for email attachments
- Preparing PDFs for upload to forms with size limits
- Working with legal, medical, or financial documents
- When you need compression on a public or shared computer
Frequently Asked Questions
Is it really private? Do files get uploaded?
Yes, it's truly private. Files are never uploaded to any server. All processing happens in your browser using JavaScript and WebAssembly. You can verify this by disconnecting from the internet after the page loads — the tool will still work.
How much can I compress my PDF?
Compression results vary depending on the PDF content. Documents with images typically see larger reductions (30-70%), while text-heavy PDFs may see smaller improvements (5-20%). The Standard mode preserves quality, while Aggressive mode prioritizes size over appearance.
Does it work on large PDFs?
Yes, but very large files (100MB+) may take longer to process since everything runs in your browser. For optimal performance, we recommend files under 50MB. Processing time depends on your device's capabilities.
Is there a free limit?
Standard compression is completely free with no limits. Aggressive compression mode (Beta) is also free for individual files. Batch processing of multiple files uses tokens for files beyond the free tier.