Name

Expires

Synopsis

The Expires header gives a date and time at which the response is no longer valid. This allows clients such as your browser to cache a copy and not have to ask the server if it is still valid until after this time has expired.

Chapter 7 discusses how the Expires header is used—in particular, how it relates to caches and having to revalidate responses with the origin server.

Type

Entity header

Basic Syntax

Expires: HTTP-date

Example

Expires: Thu, 03 Oct 1997 17:15:00 GMT

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