can be used to make a request method conditional on not matching any of the current entity-tag values for representations of the target resource.
Quick facts
Description
can be used to make a request method conditional on not matching any of the current entity-tag values for representations of the target resource.
Syntax
If-None-Match: "33a64df5"
Related status codes
Frequently asked questions
can be used to make a request method conditional on not matching any of the current entity-tag values for representations of the target resource.
It is classified as a request header and can appear in requests or responses depending on context.
Sources & standards
Updated 2026-08-18
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