HTTP Header Checker
Check the HTTP response headers for any URL, including server, caching and security headers like HSTS, CSP and X-Frame-Options.
Enter a URL to inspect its HTTP response headers and security header coverage.
The HTTP header checker fetches any URL and shows its full response headers, including the server, content type, caching and security headers like HSTS, CSP and X-Frame-Options. Enter a URL to inspect what your server is actually sending and spot missing security headers.
How to use the HTTP Header Checker
- 1Enter the URL you want to inspect.
- 2Click Check headers to fetch the response.
- 3Review the status, server and content type in the summary.
- 4Check the security header coverage and the full header list.
What HTTP headers reveal
Every page your server returns comes with HTTP headers that describe the response: the status code, content type, caching rules, compression and security policies. Inspecting them helps you debug caching problems, confirm the right status code is returned, and verify that security and performance headers are in place. This tool surfaces all of them in one view.
Why security headers matter
Headers like Strict-Transport-Security, Content-Security-Policy, X-Content-Type-Options and X-Frame-Options protect your visitors from common attacks and signal a well-run site. Missing them is a frequent finding in audits. The checker grades your coverage so you can see at a glance which security headers to add.
Headers, caching and performance
Caching headers tell browsers and CDNs how long they can store your assets, which directly affects load time and Core Web Vitals. The content type and compression headers affect how efficiently a page is delivered. Checking these helps you confirm your performance setup is doing what you expect before it shows up as a ranking issue.
Frequently asked questions
Is the HTTP header checker free?
Yes, it is free with no signup. Enter a URL and view its response headers.
What are HTTP security headers?
Security headers such as HSTS, Content-Security-Policy, X-Content-Type-Options and X-Frame-Options instruct the browser to enforce protections that defend visitors against common web attacks.
Why should I check my response headers?
To debug caching and status-code issues, confirm HTTPS and compression are working, and verify that recommended security headers are present.
Do security headers affect SEO?
Indirectly. They improve safety and trust, and HTTPS is a confirmed ranking signal. A secure, well-configured site is part of technical SEO health.
What status code should a normal page return?
A working page should return 200. Redirects return 3xx, and missing or broken pages return 4xx or 5xx. The checker shows the exact status.
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