HTTP Headers Viewer
Inspect HTTP response headers of any URL. Check security headers, caching policies and server configuration with a detailed security score.
Enter a URL above to inspect its HTTP response headers.
Security headers
Security headers like CSP, HSTS and X-Frame-Options protect against common web attacks including XSS, clickjacking and protocol downgrade attacks.
HEAD vs GET
HEAD requests only fetch headers without downloading the body, making them faster. Some servers may return different headers for GET requests.
Caching headers
Headers like Cache-Control, ETag and Last-Modified control how browsers and CDNs cache resources, affecting performance and freshness.
How to Use HTTP Headers Viewer
The HTTP Headers Viewer lets you inspect the full set of response headers returned by any URL. Analyze security headers, caching policies, CORS settings, and server configurations without needing developer tools. This is invaluable for debugging web applications and auditing security configurations.
Open the HTTP Headers Tool
Navigate to the HTTP Headers Viewer from the cybersecurity tools menu. The tool provides a URL input field and options for customizing the request.
Enter the Target URL
Type or paste the full URL you want to inspect, including the protocol (http:// or https://). The tool will make a request to that URL and capture all response headers.
Send the Request
Click the check button to send an HTTP request to the target URL. The tool captures the complete set of response headers returned by the server.
Review Response Headers
Examine each header name-value pair in the results. Key security headers to look for include Content-Security-Policy, X-Frame-Options, Strict-Transport-Security, and X-Content-Type-Options.
Identify Missing Headers
Check for the absence of important security headers that should be present. Missing headers represent potential security gaps in the server configuration.
Common Use Cases
Security Header Auditing
Verify that production websites include all recommended security headers such as CSP, HSTS, X-Frame-Options, and Referrer-Policy.
Debugging Caching Issues
Inspect Cache-Control, ETag, and Expires headers to troubleshoot why content is being served stale or not cached at all.
CORS Configuration Verification
Check Access-Control-Allow-Origin and related CORS headers to diagnose cross-origin request failures in web applications.
Performance Optimization
Review compression headers (Content-Encoding), keep-alive settings, and transfer encoding to identify opportunities to improve page load speed.
Pro Tips
- -Look for Strict-Transport-Security (HSTS) to confirm a site enforces HTTPS. Missing HSTS means users could be vulnerable to downgrade attacks.
- -Check Content-Security-Policy to understand what resources a page is allowed to load; a missing CSP header increases XSS risk significantly.
- -The Server header often reveals the web server software and version; hiding this header is a common security hardening practice.
- -Compare headers between staging and production environments to catch misconfigurations before they reach live users.
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