From
IANA permanent
request
RFC 9110
2 spellings
Declared by 4 providers across 13 published specification files in the APIs.io network.
A count here is providers whose published contract declares this header — not
providers who send it. Response headers set at the edge rarely appear in an OpenAPI at all, so a low
number can measure documentation practice rather than deployment.
Spelled 2 ways
HTTP field names are case-insensitive (RFC 9110 §5.1), so every spelling below is the same header on the wire. A contract is not the wire: generated clients key off the string, and a developer reading two of these sees two different headers.
Fromfrom
The registry
| Status | permanent |
|---|---|
| Reference | RFC 9110, Section 10.1.2: HTTP Semantics |
Providers declaring it (4)
bazaarvoice mailgun outdoorsy pagerduty
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