📋 HTTP Headers Inspector

Inspect all HTTP response headers for any URL. Check security headers, cache control, server info, and CORS settings.

Verify: ...
⏳ Fetching HTTP headers...

What Is an HTTP Headers Inspector?

An HTTP headers inspector makes a request to a URL and displays all response headers returned by the server — including status code, cache-control directives, content-type, server software, security headers, and CDN-specific headers. These headers control everything from browser caching to security policies to how search engines handle your pages.

Cache-Control: The Performance Header That Affects Core Web Vitals

The Cache-Control header tells browsers and CDN edge nodes how long to cache resources. Without proper caching directives, every visitor re-downloads CSS, JS, and image files on each visit. Setting long max-age values for versioned static assets dramatically improves repeat-visit performance and Core Web Vitals scores.

HSTS: Enforcing HTTPS at the Browser Level

The Strict-Transport-Security header instructs browsers to always connect via HTTPS, even before the server sends a redirect. This eliminates the latency of the initial HTTP-to-HTTPS redirect and protects against SSL-stripping attacks. Use a long max-age of at least 31536000 seconds and include subdomains.

At minimum: Strict-Transport-Security, X-Content-Type-Options, X-Frame-Options, Referrer-Policy, and a basic Content-Security-Policy. These cover the core security baseline. Use our HTTP Security Headers Scanner for a detailed audit with a letter grade.
Cache-Control headers are the biggest performance-related headers. Properly cached assets load from local browser storage, eliminating network round-trips. Compress headers also signal whether content is served compressed, reducing transfer sizes by 60–80%.
Other Free SEO Tools