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401 Unauthorized

The HTTP 401 Unauthorized client error status response code indicates that the request has not been applied because it lacks valid authentication credentials for the target resource.

This status is sent with a WWW-Authenticate header that contains information on how to authorize correctly.

This status is similar to 403, but in this case, authentication is possible.

Status

401 Unauthorized

Example response

HTTP/1.1 401 Unauthorized 
Date: Wed, 21 Oct 2015 07:28:00 GMT
WWW-Authenticate: Basic realm="Access to staging site"

Specifications

Specification Title
RFC 7235, section 3.1: 401 Unauthorized HTTP/1.1: Authentication

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari Servo
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)
Feature Android Chrome for Android Edge Mobile Firefox for Android IE Mobile Opera Mobile Safari Mobile
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)

See also

Document Tags and Contributors

 Contributors to this page: fscholz
 Last updated by: fscholz,