HTTP Header Inspector
See the exact HTTP response headers a URL returns — status code, caching, security headers (HSTS, CSP), server and content type. Great for debugging caching, redirects and security configuration. Runs server-side; nothing is stored.
- 100% free
- Secure
Why use HTTP Header Checker?
HTTP Header Checker performs a fast, secure server-side lookup and presents the results in a clear, readable format.
- Fast server-side lookup — we don't store your queries.
- Completely free, with no account, no watermarks and no usage limits.
- Handles Input: http/https URL; Output: status + response headers.
- Enter a URL.
- Works on any device — desktop, tablet and phone — and is fully keyboard accessible.
What it can do — and its limits
- Fetches a URL's HTTP response: status code, content-type, caching and security headers (HSTS, CSP and more).
- Runs as a server-side request, so it isn't affected by your browser's CORS rules.
How to use HTTP Header Checker
- Enter a URL.
- Click Check.
- See the status and every response header.
- Copy any header value.
Examples
- Verifying HSTS and CSP security headers.
- Checking cache-control on an asset.
Worked example
Input
https://example.com
Output
200 OK · content-type: text/html · strict-transport-security present · cache-control: max-age=3600.
Supported formats & limits
- Input: http/https URL
- Output: status + response headers
Limitations
- Reads the immediate response (redirects are shown, not followed).
- Some servers vary responses by user agent or region.
Common problems & fixes
Fewer headers than expected.
Some servers only send certain headers to real browsers or hide them behind a CDN.
A redirect is returned.
You're seeing the 3xx response — follow the Location header to the final URL.
Sources & references
Last verified August 2026.
Frequently asked questions
Why a server-side request?
Browsers block reading another origin's headers (CORS), so the request runs on our server.
Does it download the page?
It reads the response headers and status, not the full page body.
Are requests stored?
No — they're processed live and not saved.