field Registered
Verified 2026-09-18 · registry updated
2026-08-28Content-Length
States the size of message content in bytes when known.
Use it for fixed-length content and let the protocol framing rules handle streamed content. Never accept conflicting length signals.
httpheaderframingsecurity
Reference (http)
Content-Length: 27
Use it for fixed-length content and let the protocol framing rules handle streamed content. Never accept conflicting length signals.
Common mistakes
- Trusting conflicting Content-Length values across a proxy chain.
IANA registry: http-fields/field-names
Registry reference: RFC 9110, Section 8.6: HTTP Semantics