Date
ResponseActiveThe Date header contains the date and time at which the message was originated, in RFC 1123 format. Servers must include Date in all responses with a few exceptions (1xx, certain 5xx). Clients and caches use Date to calculate response age (Age = now - Date) and validate cache freshness. Intermediaries must not modify Date.
Date: <day-name>, <day> <month> <year> <hour>:<minute>:<second> GMT
Description
Date is a mandatory response header for origin servers (except for 1xx informational responses and 5xx responses when the server has no clock). The value is the server's current time at the moment the response was generated. Caches use Date as the response_time baseline for freshness calculation. HTTP/2 and HTTP/3 compress common headers including Date via HPACK/QPACK.
Examples
Standard response Date
http
HTTP/1.1 200 OK
Date: Thu, 24 Jul 2025 14:30:00 GMT
Cache-Control: max-age=3600