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HTTP Header Checker

Fetch and inspect the HTTP response headers of any URL. Check status codes, security headers, caching directives, and server information instantly.

Used 44.5K times today

Note: Fetching HTTP headers from another origin is blocked by CORS in browsers. Full header checking requires a backend proxy. This tool shows important headers to look for and your browser's current settings.

How to Use HTTP Header Checker

  1. 1

    Enter the URL

    Paste the full URL you want to inspect, including https://, into the input field.

  2. 2

    Click Fetch Headers

    The tool makes a server-side request to the URL and retrieves all HTTP response headers without executing any client-side scripts on the target page.

  3. 3

    Analyse the headers

    Review the status code, server type, content type, caching headers, and security headers such as Content-Security-Policy, Strict-Transport-Security, and X-Frame-Options.

Frequently Asked Questions

Why are HTTP security headers important?
Security headers such as Content-Security-Policy, X-Content-Type-Options, and Strict-Transport-Security instruct browsers to enforce protection policies that mitigate XSS, clickjacking, and downgrade attacks.
What does a 301 vs 302 redirect header mean?
A 301 is a permanent redirect that passes link equity and signals to search engines that the URL has moved forever. A 302 is temporary and search engines will continue to index the original URL.
Can I use this tool to check CORS headers?
Yes. The tool displays all response headers including Access-Control-Allow-Origin and other CORS-related headers that control cross-origin resource sharing behaviour.

About HTTP Header Checker

The HTTP Header Checker on Utilko performs a live server-side fetch of any URL and returns the complete set of HTTP response headers in a readable format. This is invaluable for debugging redirect chains, verifying caching strategies, and auditing security headers without needing browser developer tools or command-line utilities like curl.

Security professionals use HTTP header checks as a first step in assessing a site's security posture — missing headers like Content-Security-Policy or Strict-Transport-Security are common vulnerabilities that this tool quickly exposes. Developers use it to confirm that CDN, proxy, and server configurations are behaving as expected.

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