WWW-Authenticate

Response headers

States which authentication scheme to use; it accompanies a 401.

On the wireWWW-Authenticate: …
CategoryResponse headers

Headers the server attaches when it answers.

How to read this

  • The first digit of a status code carries the meaning: 4 means the request, 5 means the server.
  • 404 means "not there"; 403 means "there, but not for you". Swapping them makes debugging slower.
  • Header names are case-insensitive — Content-Type and content-type are the same header.
  • Caching and CORS problems usually come down to one header line, visible in the browser’s network tab.

Frequently asked questions

Q. What does HTTP WWW-Authenticate mean?

States which authentication scheme to use; it accompanies a 401.

Q. What does WWW-Authenticate look like on the wire?

It travels as WWW-Authenticate: …

Q. Where does WWW-Authenticate appear?

In response headers.

Q. What group does WWW-Authenticate belong to?

The response headers group; the rest of that group is listed further down.

Same group

Reference docs