HTTP Header Checker
View all HTTP response headers from any website.
HTTP Headers in action
Your site passes a security audit on one URL but fails on another. Fetch both with the headers tool and diff them side by side — the difference is usually one missing header added by a plugin or reverse proxy, and the tool makes that difference obvious in seconds.
Frequently Asked Questions
What are HTTP headers?
HTTP headers contain metadata about requests and responses between a browser and server.
How do I view HTTP response headers online for free?
Type a URL and run the check — all response headers (server, cache-control, content-type, security headers) are displayed in a table. It works for any public website without installing curl or developer tools.
Which HTTP security headers should every site have?
At minimum: Content-Security-Policy, Strict-Transport-Security (HSTS), X-Content-Type-Options, and X-Frame-Options. Our tool highlights which of these are present and which are missing, so you can close the gaps.
What does the cache-control header actually do?
Cache-control tells browsers and CDNs how long to store a response (max-age) and whether it can be shared (public/private). Wrong values cause stale content or excessive re-downloads — the two most common page-speed complaints.