field Registered
Verified 2026-09-18 · registry updated
2026-08-28Accept-Language
Gives the client's language preferences for the response.
Use it as a preference, not an absolute identity signal. Let users override language selection and send Vary: Accept-Language for cacheable variants.
httpheadercontent-negotiationi18n
Reference (http)
Accept-Language: en-US, de;q=0.8
Use it as a preference, not an absolute identity signal. Let users override language selection and send Vary: Accept-Language for cacheable variants.
Common mistakes
- Using it to guess a user's nationality or permanently pinning the locale.
IANA registry: http-fields/field-names
Registry reference: RFC 9110, Section 12.5.4: HTTP Semantics