PasteGuard

Masks names, emails, and other personal data with placeholders before your prompt reaches ChatGPT, Claude, or Gemini.

PasteGuard replaces personal data in your prompt with placeholders before it reaches an AI chat. The AI sees only the placeholders; when the answer comes back, PasteGuard shows your real values again. Works on ChatGPT, Claude, and Gemini. How it works: • Select text and mask it manually with a keyboard shortcut or the right-click menu. This always works and needs no server. • Or connect your own self-hosted PasteGuard server for automatic detection of names, emails, phone numbers, addresses, and more. • On submit, detected data is replaced with placeholders like [[EMAIL_1]]. The platform only ever receives the masked text. • Responses are un-masked locally, so you read your real values instead of the placeholders. Privacy: • Fresh installs use your local PasteGuard server at http://localhost:3000 for automatic detection. You can configure your own server endpoint or disable automatic detection for manual-only masking. • Automatic detection sends your draft to your configured PasteGuard server. Manual masking runs locally in your browser. • Placeholder mappings are stored locally in your browser and expire after 30 days. Only your preferences sync; personal data never does. The PasteGuard server is open source (Apache 2.0): https://github.com/sgasser/pasteguard The browser extension is currently closed source.