All HTTP Status Codes
401

Unauthorized

4xx Client Error

What It Means

The request requires user authentication. The client must authenticate itself.

When You'll See It

Returned when an API request is missing or has an invalid authentication token.

Related Status Codes

Frequently Asked Questions

What does HTTP 401 mean?

HTTP 401 Unauthorized means: The request requires user authentication. The client must authenticate itself.

When does a server return 401?

Returned when an API request is missing or has an invalid authentication token.

Is 401 a client error or server error?

HTTP 401 is a Client Error (4xx) response. This means the issue is on the client side — the request was incorrect or unauthorized.

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