Claude: API error 401 (unauthorized)

Your API key is missing, expired, malformed, or does not have permission for the model you tried to call. 401 is always an authentication problem — never a server issue.

Is Claude down right now? Check the live Claude status page for Anthropic incidents and what to use on Krater meanwhile.

More Claude error guides

Internal Server Error 500
Network unknown error
CLI: 500 (Claude Code)
Claude not working at all
High Demand / Capacity Limit
Conversation Too Long
API Rate Limit Error (429)

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