Security for browser-based PDF redaction
Security for browser-based PDF redaction means no document uploads, offline-verifiable processing, and manual review before export.
Your files stay on your device
Your PDF is opened and processed directly in your browser.
It is never:
- uploaded
- stored on a server
- sent to any external service for processing
No external processing
hddn does not send your files to:
- AI services
- external APIs
- remote servers for processing
Everything happens locally on your device.
In-browser processing
When you open the site, your browser downloads the tool.
After that, all work happens inside your browser using your device.
Your file is handled temporarily in memory while you use the tool.
When you leave the page, the file is no longer kept by the app.
Offline mode - works even in airplane mode
You can preload tools, turn off Wi-Fi, refresh /redact, and keep working offline.
Offline mode stores only app and runtime assets in browser cache.
It does not store your PDF, extracted text, previews, redactions, or exported files.
The Trust Center explains how to test this by disconnecting from the internet.
How to verify no-upload processing
You can check the security claim instead of only reading it.
- Open /redact while connected.
- Choose “Load offline tools.”
- Turn off Wi-Fi, disable cellular data, or enable airplane mode.
- Refresh /redact.
- Open and redact a PDF while disconnected.
For scanned PDFs, load OCR tools before disconnecting.
No file storage
We do not store your documents in:
- databases
- browser storage
- any persistent system
Browser storage may contain only reusable tooling assets if you enable offline mode.
User control
You review all changes before exporting.
Nothing is removed unless you confirm it.
Limitations
hddn helps identify sensitive data, but it may not detect everything.
You are responsible for reviewing your document before sharing it.
Summary
- Your files stay on your device
- No uploads
- No external processing
- You control what is removed