HEAD requests the headers that are returned if the specified resource would be requested with an HTTP
GET method. Such a request can be done before deciding to download a large resource to save bandwidth, for example.
A response to a
HEAD method should not have a body. If so, it must be ignored. Even so, entity headers describing the content of the body, like
Content-Length may be included in the response. They don't relate to the body of the
HEAD response, which should be empty, but to the body of similar request using the
GET method would have returned as a response.
If the result of a
HEAD request shows that a cached resource after a
GET request is now outdated, the cache is invalidated, even if no
GET request has been made.
|Request has body||No|
|Successful response has body||No|
|Allowed in HTML forms||No|
|RFC 7231, section 4.3.2: HEAD||Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content|
|Android webview||Chrome for Android||Edge Mobile||Firefox for Android||Opera for Android||iOS Safari||Samsung Internet|
© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.