HTTP Header Analyzer
Inspect HTTP response headers to understand browser instructions, security controls, cache behavior, and technical signals before changing server or CDN configuration.
What this tool checks
Response Header Inventory
Reviews the HTTP response headers returned by the server so you can see which instructions are actually being sent with the page. Use the inventory to compare the live response with your intended server, application, proxy, or CDN configuration before treating a missing or unexpected field as an error.
Security Header Configuration
Checks for security-related headers such as HSTS, CSP, and X-Frame-Options. The analyzer helps you spot missing or conflicting directives, but the correct setting depends on how your site loads resources, handles framing, and serves secure traffic. Review each finding in the context of your application before applying a stricter policy.
Caching Instructions
Evaluates cache-related response headers so you can understand whether browsers and intermediaries are being told to reuse, revalidate, or avoid storing a response. Treat the result as a configuration review rather than a performance guarantee, because appropriate caching depends on how often the content changes and whether the response is user-specific.
Why HTTP Headers Deserve a Technical Review
HTTP response headers influence how browsers, caches, and other clients handle a page before the body is rendered. Security directives can restrict risky behavior, while cache instructions can control reuse and freshness. A header is only useful when it matches the site's actual architecture, so the practical goal is to identify omissions, contradictions, or unintended defaults and then fix them at the layer that owns the response.
Frequently asked questions
Which HTTP headers should I review first?
Start with the headers that affect the issue you are diagnosing. For security review, inspect HSTS, CSP, and X-Frame-Options. For cache behavior, inspect Cache-Control and related response instructions. There is no single header that has the biggest impact in every setup, so prioritize unexpected or missing directives that conflict with the page's intended behavior.
Where should I change HTTP response headers?
Change them at the layer that actually generates or modifies the response. Depending on your stack, that can be the web server, application framework, reverse proxy, CDN, or another edge configuration. After making a change, inspect the live response again to confirm that downstream layers did not overwrite or duplicate the directive.