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Privacy

Privacy for local PDF redaction

Last updated: May 11, 2026

Privacy for local PDF redaction starts with browser-only processing. hddn does not upload, store, or send your files away for redaction.

Files

Your PDF stays on your device.

We do not upload, store, or send your files anywhere for processing.

Analytics

Google Analytics is optional.

It only runs if you accept it, and it is not used to access your documents.

Control

Review stays in your hands.

You should always review the document before exporting and sharing it.

Offline mode

Only tooling is cached.

Offline mode can store the app shell, PDF engine, OCR files, fonts, and detection dictionaries in your browser cache. It does not store your PDFs, previews, extracted text, redactions, or exports.

Short version

Your PDF stays on your device.

We do not upload, store, or send your files anywhere.

We only use Google Analytics, with your consent, to understand basic site usage.

Offline mode stores app tooling files only, not document contents.

What we do

hddn is a tool that runs in your browser. When you use it, your PDF is opened and processed directly on your device.

We do not:

  • upload your files
  • store your files
  • send your files to any server
  • use remote AI services or external APIs to process your files

Any detection used by the app runs locally in your browser on your device.

Everything related to your document stays on your device.

How the tool works

When you open the site, your browser downloads the code needed to run the tool. After that, your browser can open and edit your PDF locally.

This means:

  • your file does not leave your device
  • no one else can access your document through hddn

Analytics

We use Google Analytics to understand how the site is used.

This helps us answer questions like:

  • how many people use the site
  • which pages are visited

Analytics is only enabled if you accept it.

We do not use analytics to access or analyze your files.

Cookies

Cookie name

hddn_analytics_consent

Stores

accepted or declined

Used for

remembering your analytics preference

  • does not track your activity across sites
  • is used only to remember your preference

Data storage

We do not store your files in:

  • localStorage
  • IndexedDB
  • any database

Your PDF is handled temporarily in memory while you use the tool. Once you close the page or export your file, it is no longer kept by the app.

If you use offline mode, the browser may keep app code, PDF runtime files, OCR language files, fonts, and detection dictionaries in CacheStorage or runtime caches so the tool can reload offline. That cache is for tooling only, not your documents.

See the Trust Center for a plain-English explanation of offline mode and how to verify it yourself.

Hosting and infrastructure

The website is hosted on GitHub Pages and served through Cloudflare.

These services may process basic technical data such as:

  • IP address
  • request metadata

This is required to deliver the website.

Your responsibility

hddn helps you remove sensitive data, but it does not guarantee that all sensitive information will be detected.

You should always review the document before exporting and sharing it.

Contact

If you have questions about privacy, contact:

[email protected]

Linas Jonas Zilinskas