How to use the HTTP header checker
- Type or paste a full URL into the box, for example https://example.com. If you skip the protocol, the tool adds https:// for you.
- Click the Check headers button. The request runs against our check endpoint and returns within a second or two.
- Read the results: status code, content type, server software, content length, response time and final URL.
- If the target redirected, the redirect chain is listed hop by hop so you can see every step and its status code.
What HTTP headers tell you
Every time a browser requests a page, the server answers with a block of metadata called response headers. They describe how to handle the content that follows — what type it is, how large it is, whether it is cached, and which server software produced it. Reading them helps you debug redirect loops, confirm a CDN or reverse proxy is working, and verify that a server is sending the right content type.
Common status codes explained
| Status | Meaning |
|---|---|
| 200 | The request succeeded and the page was returned. |
| 301 / 302 | The URL moved permanently or temporarily; a redirect is in place. |
| 404 | The resource was not found. |
| 500 | The server hit an internal error. |
When to check response headers
Webmasters check headers after launching a redirect, switching hosting, or adding a CDN to confirm everything resolves correctly. SEO specialists use the redirect chain to make sure a 301 is a single clean hop rather than a chain that wastes crawl budget. Developers inspect the content type and server values when an API or asset is behaving unexpectedly. Running the check here is fast and requires no account.
How to read the results
The status row is the first thing to check — 200 means the page is reachable. The content type tells you whether the server is sending HTML, JSON, an image or a download, and the server row names the software or CDN that answered. The content length is the size of the body in bytes, which is handy for spotting responses that are unexpectedly large or empty. Finally, the response time shows how long the full round trip took, so you can spot slow upstream servers at a glance.