What are HTTP headers?

HTTP headers are metadata sent with every web request and response. They control caching, security, content type, redirects, and more.

What is a 301 redirect?

A 301 redirect is a permanent redirect telling browsers and search engines that a page has permanently moved to a new URL.

What does the HSTS header do?

Strict-Transport-Security tells browsers to only connect over HTTPS for a set max-age, preventing downgrade and cookie-hijacking attacks. Example: Strict-Transport-Security: max-age=31536000; includeSubDomains.

What is the difference between Cache-Control and Expires?

Both control caching, but Cache-Control (HTTP/1.1) uses relative directives like max-age=3600 and takes precedence over the older Expires header, which gives an absolute date. Modern setups rely on Cache-Control.

Why should I check my security headers?

Headers like Content-Security-Policy, X-Content-Type-Options and X-Frame-Options harden a site against XSS, MIME sniffing and clickjacking. Inspecting the response confirms they are actually being sent.

Does this fetch headers from my browser or your server?

ToolsHub requests the URL from its servers and shows the raw response headers it receives. Results reflect what the origin sends to a server, which can differ from headers added by a local proxy.

What does the Content-Type header tell me?

It declares the media type and often charset of the response body, for example text/html; charset=utf-8. Browsers use it to decide how to render content, so a wrong value can cause downloads or garbled text.

HTTP Headers Checker — View Response Headers

How to use HTTP Headers Checker

The HTTP Headers tool fetches any URL and shows the full set of response headers the server returns, including status code, content type, caching directives, security headers and redirects. Headers control how browsers cache, secure and render a page, so inspecting them is essential when debugging why a resource is not being cached, why a security policy is not applying, or whether a redirect chain is configured correctly. The tool follows redirects and reports each hop so you can see the complete journey from the requested URL to the final response.

Enter the full URL you want to inspect, including https://.
Click Fetch to request the URL and capture its response headers.
Review the status code and each header returned by the server.
Follow any redirect chain shown to confirm the final destination.
Check security and caching headers against your expectations.

Key security headers to look for

Modern sites rely on a handful of response headers to harden the browser against common attacks. Strict-Transport-Security forces HTTPS, Content-Security-Policy restricts which scripts and resources may load, X-Content-Type-Options stops MIME sniffing, and X-Frame-Options or a frame-ancestors policy prevents clickjacking. If these headers are missing or misconfigured, a security scanner will flag the site, so verifying them here is a quick way to confirm your hardening is actually being sent to clients.

Important security headers
Header	Protects against
Strict-Transport-Security	Protocol downgrade / SSL stripping
Content-Security-Policy	Cross-site scripting (XSS)
X-Content-Type-Options	MIME-type sniffing
X-Frame-Options	Clickjacking

Caching and content headers

Cache-Control, ETag and Expires headers tell browsers and CDNs how long they may reuse a response, which directly affects page speed and server load. Content-Type declares the media type and character set so the browser renders the body correctly. If a page seems to ignore your updates, an aggressive Cache-Control max-age is often the cause; if text appears garbled, a missing or wrong charset in Content-Type is the usual culprit. Reading these headers turns guesswork into a definitive diagnosis.

Glossary

Status code: A three-digit number such as 200, 301 or 404 that summarises the result of an HTTP request.
Cache-Control: A header that dictates how and for how long a response may be cached.
ETag: A validator token that lets a client revalidate a cached resource without re-downloading it.
CSP: Content-Security-Policy — a header restricting which resources a page may load to mitigate XSS.
Redirect: A 3xx response that points the client to a different URL to continue the request.

Related Network & DNS

Website Up or Down Checker

Check if a website is down for everyone or just you. Instantly test whether any URL is reachable and see its HTTP status code in real time.

Redirect Checker

Trace the full redirect chain of any URL. See every 301, 302, 307 redirect hop, final destination, and HTTP status codes.

DNS Lookup Tool

Look up DNS records for any domain — A, AAAA, MX, NS, TXT, CNAME, SOA, and CAA records. Free, instant results pulled from authoritative nameservers.

SSL Certificate Checker

Check SSL/TLS certificate validity, issuer, expiry date, and remaining days for any domain to prevent HTTPS outages and certificate trust errors.

TLS Version Checker

Check which TLS protocol versions a server supports, from legacy TLS 1.0 and 1.1 to modern TLS 1.2 and 1.3. A free TLS version checker that runs a real handshake.

Port Checker

Check if a TCP port is open or closed on any host. Test firewall rules and server accessibility instantly — great for debugging network services.

Explore all Network & DNS.

HTTP Headers Checker

How to use HTTP Headers Checker

Key security headers to look for

Caching and content headers

Glossary

Related reading

Frequently Asked Questions

Why use HTTP Headers Checker?

Common use cases

Get weekly tool tips & updates

Related Network & DNS