Understand HTTP response headers and use a header lookup to investigate caching, content type, redirects, and delivery settings.
How to Read HTTP Headers from a URL
When a browser requests a page, the server returns more than visible HTML. It also sends HTTP response headers: compact information about the response, its type, caching behavior, and delivery details. Reading them helps when a page is not caching as expected, downloads instead of displaying, or behaves differently across environments.
Useful headers
Content-Type indicates whether the response is HTML, JSON, an image, or another type. Location matters when a server redirects a request. Cache-related headers such as Cache-Control, Expires, and ETag help explain reuse and revalidation. The Vary header shows when a response can depend on selected request headers.
How to look up headers
- Copy the URL you want to investigate.
- Open Bagiqo's HTTP headers lookup.
- Enter the URL and inspect the returned list.
- Review the status and redirect location before interpreting other headers.
Use a public URL that can be reached by the service. Private or login-protected addresses may not represent the request you need to debug.
Use headers as evidence
Headers are clues, not a complete performance audit. Compare a working URL with a problematic one, record differences, and then check your server or application configuration. For a quick first look, use Bagiqo's HTTP headers lookup before changing cache rules.