Prompt Seal

Keep secrets out of AI prompts. Detect and redact sensitive data before sending.

🦭 Prompt Seal — Keep secrets out of AI prompts. Prompt Seal is a free, local-first browser extension that detects and redacts sensitive data before you send prompts to AI assistants. 🔒 WHAT IT DOES Prompt Seal scans your messages in real time — before they reach any AI chatbot. If it finds API keys, passwords, tokens, or personal data, it blocks the send and lets you review or auto-redact. ⚡ DETECTION ENGINE • 85 regex patterns covering cloud credentials, API keys, auth tokens, database URLs, private keys, webhooks, and package registry tokens • 13 Shannon entropy detectors — catches unknown secrets in ENV files, JSON, YAML, TOML, XML, CLI flags, URLs, base64, hex strings, and PEM keys • PII protection — credit cards, SSNs, IBANs, passport numbers, phone numbers, and email+password combos • Smart filtering — structural fields, well-known annotations, and low-entropy values are excluded to minimize false positives 🛡️ HOW IT WORKS 1. Type your prompt — write normally in any supported AI chat 2. Seal scans instantly — 85+ patterns and entropy analysis check every character before the message sends 3. Threats neutralized — get a warning modal with details, or enable auto-redact for zero-friction protection Secrets are replaced with [REDACTED] tags. You choose: Cancel, Send Anyway, or Redact & Send. 🌍 12 LANGUAGES Auto-detected from your browser settings. All UI elements — popup, modal, warnings, severity labels — are fully translated. ⚙️ FEATURES • Real-time scanning with MutationObserver + event listeners + polling fallback • Send interception on Enter key, click, and form submit (capture phase) • Warning modal in isolated Shadow DOM (won't break page styles) • Auto-redact mode — secrets replaced silently, message sent automatically • Floating indicator badge with secret count (🦭) • Light and dark theme • Protection toggle • Scan statistics (total scans, threats blocked) 🔐 PRIVACY • 100% local — all scanning runs in your browser • Zero data collection — no analytics, no tracking, no cookies • No backend — no servers, no cloud APIs, no external requests • No prompt storage — scanned content is never saved • Permissions: storage + activeTab only • No telemetry. Ever. Built for developers and security-conscious teams who use AI tools daily.