provides a timestamp indicating the date and time at which the origin server believes the selected representation was last modified, as determined at the conclusion of handling the request.
Quick facts
Description
provides a timestamp indicating the date and time at which the origin server believes the selected representation was last modified, as determined at the conclusion of handling the request.
Syntax
Last-Modified: Mon, 17 Aug 2026 10:00:00 GMT
Related status codes
Related headers
Frequently asked questions
provides a timestamp indicating the date and time at which the origin server believes the selected representation was last modified, as determined at the conclusion of handling the request.
It is classified as a representation header and can appear in requests or responses depending on context.
Sources & standards
Updated 2026-09-13
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