Resources > HTTP request headers > If-Modified-Since

HTTP request headers

A request headers is an HTTP header that the client sends to the server.

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logo If-Modified-Since

ID: 27
TypeStandard
SubypeHTTP
Related headersAccept, Accept-Encoding, Accept-Charset, Accept-Language, Authorization, Connection, Content-Length, Content-Type, Cookie, Dnt, Expect, From, Host, If-None-Match, Prefer, Range, Referer, User-Agent, X-Auth-Token, X-Request-Id
Last seen2021-08-30 06:35:08
NoteAllows a 304 Not Modified to be returned if content is unchanged.
Syntax
If-Modified-Since: <day-name>, <day> <month> <year> <hour>:<minute>:<second> GMT

Example header value:
Sun, 28 Mar 2021 04:51:35 GMT

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