HTTP 401 Unauthorized — Meaning

401 Unauthorized means authentication is required or the credentials supplied are invalid; retry with proper credentials. Unlike 403, it implies access is possible once authenticated.

Key facts

Frequently asked questions

What does 401 mean?

Authentication is missing or invalid; supply valid credentials.

401 vs 403?

401 = not authenticated; 403 = authenticated but lacking permission.

Related pages

• HTTP 200 OK
• HTTP 301 Moved Permanently
• HTTP 403 Forbidden
• HTTP 404 Not Found
• HTTP 429 Too Many Requests
• HTTP 500 Internal Server Error
• HTTP 502 Bad Gateway
• HTTP 503 Service Unavailable

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