HTTP Header Checker

Inspect HTTP response headers for any URL. Check security headers, caching policy, server info, and more.

How to Check HTTP Headers

Enter any URL and click Inspect to see all HTTP response headers returned by the server. The results show every header name and value in a clean table format. A dedicated security headers section uses green checkmarks and red indicators to show which recommended security headers are present and which are missing. This includes Content-Security-Policy, Strict-Transport-Security (HSTS), X-Frame-Options, X-Content-Type-Options, Referrer-Policy, and Permissions-Policy. Use this tool to audit your own site or analyze competitors.

Why HTTP Headers Matter for Security

HTTP security headers are your first line of defense against common web attacks. Content-Security-Policy (CSP) prevents cross-site scripting (XSS) by restricting which scripts can run. Strict-Transport-Security (HSTS) forces browsers to use HTTPS, preventing downgrade attacks. X-Frame-Options blocks clickjacking by preventing your site from being embedded in iframes. X-Content-Type-Options stops MIME-type sniffing attacks. Without these headers, your site is vulnerable to well-known attacks that security scanners will flag. Most take only a few lines of server configuration to add.

Frequently Asked Questions

At minimum: Content-Security-Policy, Strict-Transport-Security, X-Content-Type-Options (set to nosniff), X-Frame-Options (set to DENY or SAMEORIGIN), and Referrer-Policy. These protect against XSS, clickjacking, MIME sniffing, and information leakage.

HTTP Strict Transport Security (HSTS) tells browsers to always use HTTPS when connecting to your site, even if the user types http://. This prevents SSL stripping attacks where an attacker downgrades a secure connection to plain HTTP.

HEAD requests return only the headers without downloading the page body, making the check faster and more efficient. Response headers are the same as those returned by a GET request.