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HEAD

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The HTTP HEAD method 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If the result of a HEAD request shows that a cached resource after a GET request is now outdated, the cache is invalidated, even if no GET request has been made.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
Safe Yes
Idempotent Yes
Cacheable Yes
Allowed in HTML forms No

Syntax

HEAD /index.html

Specifications

Specification Title
RFC 7231, section 4.3.2: HEAD Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari Servo
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)
Feature Android Chrome for Android Edge Mobile Firefox for Android IE Mobile Opera Mobile Safari Mobile
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)

See also

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