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Content-Language

IANA permanent response RFC 9110 reached by regulation 2 spellings

Declared by 16 providers across 4207 published specification files in the APIs.io network.

What this header is for, and how to use it →

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.

Content-Languagecontent-language

Reached by regulation

Basis: inferred. Nothing requires this header. The connection is inferred. Observable at the edge, without credentials.

european-accessibility-act section-508

The registry

Status	permanent
Reference	RFC 9110, Section 8.5: HTTP Semantics

Providers declaring it (16)

amazon-s3 aws-s3 ccp-games cdk-global ebay edamam-recipes engineering-platform eve-online kpn microsoft-azure oracle oracle-hospitality picker spektr viagogo visa

Explore

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