HTTP Headers Checker

Inspect server response headers, verify security policies, and debug connection status codes instantly.

Status: 200 OK

Protocol: HTTP/1.1 (Implicit)

Security Analysis

HSTS

Missing

X-Frame-Options

Missing

Content-Type

Unknown

CORS (Access-Control)

Restricted

Raw Response Headers

Header Name	Value

Understanding HTTP Headers

HTTP headers are the core mechanism used by web servers and browsers to exchange information about the resource being fetched. When you visit a website, your browser sends a request, and the server replies with both the content (HTML, Images) and a hidden list of "Headers". These headers dictate how the content should be cached, secured, and handled.

            Why use this tool? Developers use header checkers to debug caching issues, verify that security protocols like HSTS are active, and ensure that the correct Content-Type is being served to prevent rendering errors.
        

Critical Headers to Monitor

Strict-Transport-Security (HSTS): This header tells the browser to only communicate with the server using HTTPS, preventing man-in-the-middle attacks. It is a critical security component.
Cache-Control: Determines how long a browser or CDN should store the file. Incorrect settings here can lead to users seeing outdated content or overloading your server.
X-Frame-Options: Controls whether your site can be embedded in an <iframe> on another site. Setting this to DENY or SAMEORIGIN prevents "Clickjacking" attacks.
Access-Control-Allow-Origin (CORS): Defines which domains are allowed to access resources on your server. This is vital for API security.

How to Use This Checker

Simply enter the full URL (including https://) into the input field above. The tool will perform a HEAD request to the server and parse the response.

Troubleshooting Connection Errors

Note on CORS: Because this tool runs entirely in your browser (client-side), it adheres to Cross-Origin Resource Sharing (CORS) policies. If you try to check a major site like google.com, it may fail because Google blocks client-side scripts from reading their headers. This is a security feature of the web, not a bug in the tool. This tool works best for checking your own APIs or websites configured to allow cross-origin requests.