Overview
HeaderCheck is a lightweight, privacy-respecting Chrome extension that analyzes HTTP response headers for the active tab and evaluates a site's security and privacy posture.
It uses a deterministic weighted scoring model (SCM-2025.1) to calculate a 0–100 score based on the presence and validity of key security headers, including CSP, HSTS, COOP, COEP, CORP, Referrer-Policy, Permissions-Policy, X-Frame-Options, and X-Content-Type-Options.
• Instant analysis
• No remote calls or telemetry
• Graded vs informational headers for clarity
• Clean, minimal interface
• Focused on modern browser security and privacy best practices
• EU-aligned philosophy emphasizing transport integrity and referrer minimization
HeaderCheck runs entirely on-device inside Chrome’s extension sandbox. No data leaves your browser, ever.
Tags
Privacy Practices
🔐 Security Analysis
This extension hasn't been security-scanned yet.
