The value of the event source's last event ID string, encoded as UTF-8.
Quick facts
Description
The value of the event source's last event ID string, encoded as UTF-8.
Syntax
Last-Event-ID: 42
Frequently asked questions
The value of the event source's last event ID string, encoded as UTF-8.
It is classified as a request header and can appear in requests or responses depending on context.
Sources & standards
Updated 2026-09-13
about this tool
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