describes what parts of a request message, aside from the method and request target, might influence the origin server's process for selecting and representing the response.
Quick facts
Description
describes what parts of a request message, aside from the method and request target, might influence the origin server's process for selecting and representing the response.
Syntax
Vary: Accept-Encoding
Related status codes
Related headers
Frequently asked questions
describes what parts of a request message, aside from the method and request target, might influence the origin server's process for selecting and representing the response.
It is classified as a response header and can appear in requests or responses depending on context.
Sources & standards
Updated 2026-08-18
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