Website Diagnostics
Free HTTP Header Checker
Review available response headers, caching directives and common security headers. Use live browser checking where permitted, or paste raw header data for reliable local analysis.
Example response
Analyzer ready
Browser limitation: many websites do not expose all response headers to cross-origin JavaScript. A failed request can be caused by CORS and does not automatically indicate a website error.
Response Headers
0 headersSecurity Header Review
0 present
0%
No analysis yet
Presence alone does not confirm that a header is configured correctly.
How To Use
Check HTTP Headers in Three Steps
Use live mode where browser access is allowed, or paste raw headers for dependable local analysis.
Enter a URL or paste headers
Choose the method that matches the data available to you.
Run the analysis
The tool organizes header names, values and common security controls.
Review before changing settings
Confirm recommendations against your server, CDN and application requirements.
Key Features
Practical Response-Header Analysis
Designed for website owners, developers, technical SEO specialists and webmasters.
Header table
View available response headers in a clean, readable table.
Security review
Check the presence of commonly reviewed browser security headers.
Copy and export
Copy the analyzed header list or download it as a TXT file.
Understanding Headers
What HTTP Response Headers Can Tell You
Headers provide technical context about how a server and browser should handle a response.
Content information
Content-Type, Content-Encoding and Content-Length describe the returned resource.
Caching behavior
Cache-Control, Expires, ETag and Last-Modified influence browser and proxy caching.
Security policies
Security headers can reduce certain browser-based risks when configured appropriately.
Common Questions
HTTP Header Checker FAQs
Quick answers about response headers, browser restrictions and interpretation.
What are HTTP response headers?
They are metadata sent with a server response. Headers can describe content, caching, redirects, cookies, security policies and server behavior.
Why does a live browser check sometimes fail?
Browsers restrict cross-origin requests and access to response headers through CORS. This limitation can prevent direct inspection even when the website itself is working normally.
Does a missing security header always mean a vulnerability?
No. It is a signal for review, not an automatic diagnosis. The correct configuration depends on the website, application, hosting stack and existing controls.
Can I analyze copied headers from cURL or browser DevTools?
Yes. Copy the raw response headers and paste them into the manual analysis mode.
Does this tool change my website?
No. It only analyzes information available in the browser or text pasted into the page.
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