Prompt Guard

Prompt Guard helps reduce accidental data leakage when using AI assistants in the browser. Before a prompt is sent, the extension detects and masks sensitive information directly on the page, with no external server involved.

It works with ChatGPT, Claude, Gemini, and Copilot. You can preview the cleaned prompt before sending, block messages that still contain secrets or personal data, and create custom replacements for terms that matter in your workflow.

Everything runs locally in Chrome. Prompt Guard is designed for privacy-conscious users, consultants, teams, and organizations that want an extra layer of protection before sharing text with AI tools.