The challenge
Generative AI tools have become essential, but using them with a contract, a medical report or a customer database means handing sensitive information to third-party servers.
For regulated sectors (legal, health, finance, public administration) that is a non-starter: privacy and compliance are not negotiable. There needed to be a way to use AI without the data ever leaving the device.
The solution
We built Ocultia, a tool that runs entirely inside the browser. Before you paste a document into ChatGPT, Claude or Gemini, it replaces private data (names, emails, IDs, IBANs, addresses) with labels, and restores them as soon as the AI is done.
Detection combines deterministic rules with a small AI model running locally. No accounts, no installation and, after the first visit, it works offline. Your documents never leave your device.
A Lostium product: concept, design, on-device AI and development, end to end.
For organizations: black out the sensitive data in your docx and pdf, with no way back.
The Enterprise version processes whole docx and pdf documents and covers sensitive data with black blocks right on the document. Unlike the browser's reversible mode, the data here is not swapped for a label: it is hidden beyond recovery.
The document keeps its formatting, tables and structure; only what had to disappear changes. Built for teams handling sensitive data at scale: a dedicated instance, deployment within the organization's own infrastructure, and data always kept within its boundaries.
Results
Where almost everyone sends data to the cloud, Ocultia runs the AI in the browser itself: privacy by design for real, not as a promise. Since launch it has drawn genuine demand and interest, and stands as living proof that we can apply AI in the most demanding settings.
Stack & data
- In-browser AI
- Local model + detection rules
- No servers
- Offline after first visit
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