What is an HTTP Header Analyzer?
An HTTP header analyzer is a comprehensive tool that examines all HTTP response headers from any webpage. It analyzes security headers (HTTPS, HSTS, CSP), caching strategies, compression, CDN usage, CORS policies, and server information to help you optimize performance and security.
Our analyzer goes beyond simple header inspection—it validates configurations against best practices, assigns security scores, detects mixed content issues, and provides actionable recommendations for improvement.
Perfect for developers, security professionals, and site administrators who need to audit web server configurations, ensure proper security hardening, and optimize caching for better performance.
Why Analyze HTTP Headers?
HTTP headers control critical aspects of web security, performance, and caching. Properly configured headers protect against attacks like XSS, clickjacking, and MITM while improving page load times through intelligent caching and compression.
Security headers like HSTS force HTTPS connections, CSP prevents cross-site scripting, and X-Frame-Options stops clickjacking attacks. Missing or misconfigured security headers leave your site vulnerable to exploitation.
Performance headers control browser caching, enable compression, and configure CDN behavior. Good caching reduces server load and speeds up repeat visits. Compression can reduce transfer sizes by 70% or more, dramatically improving load times on slow connections.
What Gets Analyzed
Security Headers
Complete security audit with scoring: HTTPS enforcement, HSTS configuration, Content Security Policy, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy, and mixed content detection.
Headers checked: Strict-Transport-Security, Content-Security-Policy, X-Frame-Options, X-Content-Type-Options, X-XSS-Protection, Referrer-Policy, Permissions-Policy
Caching Strategy
Analyzes cache configuration to determine if resources are cacheable, how long they're cached, and whether revalidation is properly configured with ETags or Last-Modified headers.
Headers checked: Cache-Control, ETag, Expires, Last-Modified, Pragma, Age
Performance Optimization
Detects compression (Gzip, Brotli), CDN usage with provider identification, transfer encoding, and connection keep-alive settings for optimal performance.
Headers checked: Content-Encoding, Transfer-Encoding, Connection, CF-Ray (Cloudflare), X-Amz-Cf-Id (CloudFront), X-Fastly-Request-Id, and more
Server Information
Identifies server type, technology stack, and framework information. Also flags potentially sensitive headers that should be hidden in production.
Headers checked: Server, X-Powered-By, X-AspNet-Version, X-Framework
CORS Configuration
Examines Cross-Origin Resource Sharing setup to verify API security and cross-domain access controls.
Headers checked: Access-Control-Allow-Origin, Access-Control-Allow-Methods, Access-Control-Allow-Headers, Access-Control-Allow-Credentials, Access-Control-Max-Age
Mixed Content Detection
Scans HTTPS pages for insecure HTTP resources that could compromise security and trigger browser warnings.
Checks for: HTTP URLs in images, scripts, stylesheets, and other resources on HTTPS pages
How It Works
- Enter any webpage URL into the analyzer
- Our tool fetches the page and captures all HTTP response headers
- Headers are analyzed across six categories: security, caching, performance, server, CORS, and mixed content
- Each category is validated against industry best practices and security standards
- A security score is calculated based on essential security header presence and configuration
- Actionable suggestions are generated for missing or misconfigured headers
- View results organized by category with detailed explanations and copy/export options
Security Headers Explained
Strict-Transport-Security (HSTS)
Forces browsers to always use HTTPS, preventing downgrade attacks and man-in-the-middle exploits. Set max-age to at least 1 year (31536000 seconds), include subdomains, and consider preload for maximum protection.
Content-Security-Policy (CSP)
Prevents XSS attacks by defining trusted sources for scripts, styles, and other resources. Start with a restrictive policy and gradually allow necessary sources. Use nonce or hash-based CSP for inline scripts.
X-Frame-Options
Prevents clickjacking attacks by controlling whether your page can be embedded in frames or iframes. Use DENY to block all framing or SAMEORIGIN to allow only same-domain framing.
X-Content-Type-Options
Prevents MIME type sniffing attacks by forcing browsers to respect declared content types. Always set to "nosniff" to block browsers from interpreting files as different types than declared.
Caching Best Practices
- Use Cache-Control instead of Expires for modern browsers—it's more flexible and precise
- Set long max-age values (1 year) for static assets like images, fonts, CSS, and JS with versioned filenames
- Use "no-cache" for HTML to force revalidation while still allowing caching with ETags
- Add ETags or Last-Modified headers to enable efficient revalidation without re-downloading
- Use "public" for resources that can be cached by CDNs and shared caches
- Use "private" for user-specific content that should only be cached in browsers
- Avoid "no-store" unless content contains sensitive information that must never be cached
- Combine Cache-Control with ETag for optimal caching: long max-age with fingerprinted filenames
Frequently Asked Questions
What is a good security score?+
A score of 80+ is excellent, indicating strong security header implementation. Scores of 60-79 are good but have room for improvement. Below 60 suggests critical security headers are missing. Aim for at least HTTPS, HSTS, and X-Frame-Options as a baseline.
Why do some headers appear missing on my site?+
Security headers must be configured on your web server or application framework. They're not added automatically. Check your server configuration (Apache, Nginx, IIS) or application middleware to add missing headers. Many hosting platforms offer easy header configuration through control panels.
What's the difference between Gzip and Brotli compression?+
Brotli is a newer compression algorithm that typically achieves 15-20% better compression than Gzip, especially for text content like HTML, CSS, and JavaScript. All modern browsers support both. Enable Brotli on your server for better performance, but keep Gzip as a fallback for older clients.
How do I fix mixed content warnings?+
Mixed content occurs when HTTPS pages load HTTP resources. Change all http:// URLs to https:// in your HTML, CSS, and JavaScript. Use protocol-relative URLs (//example.com/style.css) or HTTPS-only URLs. Most external resources now support HTTPS—update any that don't.
Should I hide my Server and X-Powered-By headers?+
Yes, for production sites. These headers reveal your technology stack to potential attackers, making targeted exploits easier. Remove or obscure Server, X-Powered-By, X-AspNet-Version, and similar headers. Security through obscurity isn't a substitute for proper security, but it reduces your attack surface.
Ready to audit your HTTP headers? Use the analyzer above to get comprehensive security and performance insights with actionable recommendations.