IconVault's Header Analyzer turns raw HTTP response headers into a clean, readable table plus an automatic security header audit. Paste a captured header block, or fetch a URL and inspect the headers the browser actually exposes. Parsing and analysis are 100% client-side.

It flags the headers that matter for web security: Strict-Transport-Security (HSTS), Content-Security-Policy, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy and cookie flags like Secure, HttpOnly and SameSite. It is free with no signup and nothing leaves your device. Honest note: the browser only exposes headers that CORS allows, so a cross-origin fetch may show fewer headers than a full raw paste from DevTools or curl.