HTTP Headers Checker
Inspect HTTP response headers online to troubleshoot caching, content types, security settings, and cross-origin configuration on websites and web servers.
The check runs from the server so browser CORS restrictions do not hide response headers.
What is HTTP Headers Checker?
The HTTP Headers Checker lets you inspect HTTP response headers returned by a website or web server. Review information related to caching, content types, redirects, security policies, and cross-origin behavior to help identify configuration issues. This free online HTTP header analysis tool is useful for web developers, server administrators, and security troubleshooting. Results may vary depending on the server response, redirects, request method, and network restrictions.
Why use this tool?
- See the headers returned by a web server.
- Review security-related headers such as CSP and HSTS.
- Diagnose caching, content type and cross-origin behavior.
How to use HTTP Headers Checker
- Step 1. Enter the target URL supported by the checker.
- Step 2. Run the request and review the returned status and headers.
- Step 3. Compare important headers with the behavior you expect from your application or server configuration.
Common use cases
Important notes
- The checker requests public websites on the standard web ports (80 and 443). Private and local addresses are blocked, and every redirect it follows is checked the same way.
- Headers can vary by path, HTTP method, CDN and authentication state.
- A missing header is not automatically a vulnerability; evaluate it against the application's requirements.
More DNS & Website Tools
HTTP Headers Checker FAQ
What is Content-Security-Policy?
CSP is a browser security policy that can restrict which resources a page is allowed to load and execute.
What is HSTS?
HTTP Strict Transport Security tells compatible browsers to use HTTPS for a domain for a specified period.