Expires

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The HTTP Expires {{Glossary("response header")}}  contains the date/time after which the response is considered expired in the context of HTTP caching.

The value 0 is used to represent a date in the past, indicating the resource has already expired.

[!NOTE] If there is a {{HTTPHeader("Cache-Control")}}  header with the max-age or s-maxage directive in the response, the Expires header is ignored.

Syntax

Expires: <day-name>, <day> <month> <year> <hour>:<minute>:<second> GMT

Directives

• <day-name>
  • : One of Mon, Tue, Wed, Thu, Fri, Sat, or Sun (case-sensitive).
• <day>
  • : 2 digit day number, e.g., “04” or “23”.
• <month>
  • : One of Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec (case sensitive).
• <year>
  • : 4 digit year number, e.g., “1990” or “2016”.
• <hour>
  • : 2 digit hour number, e.g., “09” or “23”.
• <minute>
  • : 2 digit minute number, e.g., “04” or “59”.
• <second>
  • : 2 digit second number, e.g., “04” or “59”.
• GMT
  • : Greenwich Mean Time. HTTP dates are always expressed in GMT, never in local time.

Examples

Expires: Wed, 21 Oct 2015 07:28:00 GMT

Specifications

{{Specifications}} 

Browser compatibility

{{Compat}} 

See also

• HTTP caching guide
• {{HTTPHeader("Cache-Control")}} 
• {{HTTPHeader("Age")}}