401
Unauthorized
Client ErrorAuthentication is required and has failed or has not yet been provided.
Category: 4xx Client Errors Standard: RFC 9110 First Appeared: HTTP/1.0
What is 401 Unauthorized?
HTTP 401 Unauthorized means authentication is required and has either failed or not been provided. The response should include a WWW-Authenticate header describing how to authenticate.
Client Request
Server
Request Rejected
Common Causes
Missing, expired or invalid credentials
An absent or malformed Authorization header
An expired session or access token
Wrong API key
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