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401Unauthorized

The request has no valid credentials, so the server will not process it until you authenticate.

Browse all HTTP status codes

When you see it

A missing, expired or malformed token or session. The name is a historical misnomer: 401 is about authentication, meaning who you are, not authorization, meaning what you are allowed to do.

A correct 401 includes a WWW-Authenticate header saying how to authenticate. In a browser, that header is what triggers the built-in username and password box.

What to do about it

Logging in again is the usual fix, because the common cause is an expired session. For an API, check the token has not expired, is being sent on the right header, and carries the scheme the server expects, such as Bearer.

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Status codes

69 of 69 codes. Click a row to copy it.

1xx Informational (4)
2xx Success (10)
3xx Redirection (8)
4xx Client errors (31)
5xx Server errors (16)