The HTTP 401 Unauthorized client error response status code indicates that a request was not successful because it lacks valid authentication credentials for the requested resource. This status code is sent with an HTTP response header that contains information on the authentication scheme the server expects the client to include to make the request successfully.

A 401 Unauthorized is similar to the response, except that a 403 is returned when a request contains valid credentials, but the client does not have permissions to perform a certain action.

Status

401 Unauthorized

Examples

Unauthorized request to a protected API

The following GET request is made to a URL www.example.com/admin that expects credentials in an header:

GET /admin HTTP/1.1
Host: example.com

The server responds with a 401 message and a header indicating that the request must be authenticated and that Bearer auth (an access token) is the permitted authentication scheme:

HTTP/1.1 401 Unauthorized
Date: Tue, 02 Jul 2024 12:18:47 GMT
WWW-Authenticate: Bearer

Specifications

See also

• HTTP response status codes

• HTTP authentication

• ,