What is a HTTP Header?
HTTP Headers are the request to a server for information and the resulting response. When you input an address into your browser it sends a request to the server hosting the domain and the server responds. You can see the request and response using our basic HTTP Header Viewer. The HTTP Header Viewer can be used to view the Headers or Headers and Content of any valid http:// url. When HEAD is selected the request is for the server to only send header information. A GET selection requests both headers and file content just like a browser request. Information in response headers may include
- Response status; 200 is a valid response from the server.
- Date of request.
- Server details; type, configuration and version numbers. For example the php version.
- Cookies; cookies set on your system for the domain.
- Last-Modified; this is only available if set on the server and is usually the time the requested file was last modified
- Content-Type; text/html is a html web page, text/xml an xml file.
HTTP Header Viewer
Headers Sent Request
Additional detail on HTTP Headers is available at W3 Header Field Definitions.