Is this HTTP header checker free?

Yes, completely free — no account, no subscription, no limits. Paste a URL and check its headers instantly.

What are HTTP headers?

HTTP headers are metadata lines sent by a web server with every response. They describe the content type, caching rules, security policies, encoding, server software, cookies, and more — all before the page body is transferred.

What are security headers and why do they matter?

Security headers instruct browsers to enforce protections against common attacks. Key ones include Strict-Transport-Security (HSTS, forces HTTPS), Content-Security-Policy (CSP, prevents XSS), X-Frame-Options (blocks clickjacking), and X-Content-Type-Options (prevents MIME sniffing). Missing headers are a common web vulnerability.

What cache headers should I look for?

The most important cache headers are Cache-Control (defines caching rules like max-age, no-store), ETag (a fingerprint for conditional requests), Last-Modified (timestamp for freshness checks), and Expires (legacy expiry date). Together they determine how long browsers and CDNs store your content.

Can I check redirect headers and follow redirect chains?

Yes. When a URL returns a 3xx redirect (301, 302, 307, 308), the tool shows the Location header pointing to the destination and the full redirect chain so you can see every hop from the original URL to the final destination.

Only the address or URL you type is sent to our server to fetch the public result. No private files are uploaded and nothing you enter is stored.

📋 HTTP Header Checker — Inspect Response Headers Free

Enter any URL and instantly see the full HTTP response headers returned by the server — including status code, server software, cache directives, security headers like CSP and HSTS, and any redirect chain. Our server fetches the URL on your behalf and returns the raw headers, so no browser extension or command-line tool is needed.

URL

How this works. Only the address you enter is sent to our server to fetch a public result — no private files are uploaded, and nothing you enter is stored.

About

HTTP response headers are key-value pairs sent by a web server before the page body. They tell browsers how to cache content, which security policies to enforce, what software is running, and whether the request was redirected. This tool sends your URL to our backend, which performs a real HTTP request and returns every response header exactly as the server sent it. You can inspect common headers such as Content-Type, Cache-Control, ETag, Expires, X-Frame-Options, Strict-Transport-Security (HSTS), Content-Security-Policy (CSP), X-Content-Type-Options, and more — without installing anything.

How to use

Paste or type the full URL you want to inspect into the input field (include https:// or http://).
Click "Check Headers" — our server fetches the URL and retrieves the raw HTTP response headers.
Review the HTTP status code (e.g., 200 OK, 301 Redirect, 404 Not Found) displayed at the top.
Browse all returned headers in the results table — security, cache, server, and content headers are highlighted for quick identification.
Copy any header value with one click, or copy the full response for use in reports or debugging.

FAQ

Is this HTTP header checker free?: Yes, completely free — no account, no subscription, no limits. Paste a URL and check its headers instantly.
What are HTTP headers?: HTTP headers are metadata lines sent by a web server with every response. They describe the content type, caching rules, security policies, encoding, server software, cookies, and more — all before the page body is transferred.
What are security headers and why do they matter?: Security headers instruct browsers to enforce protections against common attacks. Key ones include Strict-Transport-Security (HSTS, forces HTTPS), Content-Security-Policy (CSP, prevents XSS), X-Frame-Options (blocks clickjacking), and X-Content-Type-Options (prevents MIME sniffing). Missing headers are a common web vulnerability.
What cache headers should I look for?: The most important cache headers are Cache-Control (defines caching rules like max-age, no-store), ETag (a fingerprint for conditional requests), Last-Modified (timestamp for freshness checks), and Expires (legacy expiry date). Together they determine how long browsers and CDNs store your content.
Can I check redirect headers and follow redirect chains?: Yes. When a URL returns a 3xx redirect (301, 302, 307, 308), the tool shows the Location header pointing to the destination and the full redirect chain so you can see every hop from the original URL to the final destination.
Is my data uploaded?: Only the address or URL you type is sent to our server to fetch the public result. No private files are uploaded and nothing you enter is stored.