What are HTTP headers?

HTTP headers are metadata sent with every web request and response. They control caching, security policies, content types, and more. Security headers like Content-Security-Policy and Strict-Transport-Security help protect your site from attacks.

What is Strict-Transport-Security (HSTS)?

HSTS tells browsers to only connect to your site over HTTPS. Once set, browsers will refuse HTTP connections for the specified duration. This prevents protocol downgrade attacks.

Why should I remove the X-Powered-By header?

The X-Powered-By header reveals what backend technology you're using (e.g. PHP, ASP.NET). This information can help attackers target known vulnerabilities. Remove it in your server configuration.

What is Content-Security-Policy?

CSP is a powerful security header that tells the browser which sources are allowed to load scripts, images, styles, and other resources. It significantly reduces the risk of XSS attacks.

Why might some headers be missing from the results?

Browser CORS restrictions prevent directly reading all response headers from client-side JavaScript. Some headers may not be visible. Use a server-side tool like curl for complete header inspection.

What are HTTP response headers?

HTTP response headers are key-value pairs sent by a web server with every HTTP response. They provide information about the server, content, caching rules, security policies, and more.

What security headers should every website have?

Strict-Transport-Security (HSTS), Content-Security-Policy (CSP), X-Frame-Options, X-Content-Type-Options, and Referrer-Policy are the most important security headers for modern websites.

What does the HTTP status code mean?

200 means success, 301/302 are redirects, 404 means not found, 403 means forbidden, and 500 means server error. The status code is the first thing to check when debugging a URL.

HTTP Headers Checker — Inspect HTTP Response Headers Free

Inspect HTTP response headers for any URL. Check security headers, cache headers, content type, and server information. Free HTTP headers tool.

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What is HTTP Headers Checker — Check Security Headers Free Online?

An HTTP headers checker fetches the HTTP response headers returned by a web server for any URL. Response headers contain important information about security settings, caching behavior, content type, server software, and redirects. Our tool displays all headers in a readable format with explanations of the most important security and SEO-relevant headers.

How to Use HTTP Headers Checker — Check Security Headers Free Online

1Enter the URL you want to inspect.
2Click Check Headers to fetch the response headers.
3Review all HTTP response headers.
4Check for important security headers (HSTS, CSP, X-Frame-Options).
5Note any missing headers that should be configured.

Key Features

All HTTP response headers displayed
Security header analysis (HSTS, CSP, X-Frame-Options, etc.)
HTTP status code
Redirect chain detection
Cache-Control and Expires header analysis

Benefits

Audit security header configuration
Check if caching is properly configured
Verify content type is set correctly
Identify redirect issues
Debug server configuration problems

Use Cases

Domain WHOIS lookup

Why Use Irreva for HTTP Headers Checker — Check Security Headers Free Online?

Audit security header configuration

Check if caching is properly configured

Verify content type is set correctly

Runs 100% in your browser — files never leave your device.

No account, no sign-up, no subscription — free forever.

Works on any device: desktop, tablet, or mobile.

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