Articles/HTTP

HTTP 401 Unauthorized — What It Means

What HTTP status code 401 Unauthorized means, when servers return it, and how to handle it correctly.

Published September 23, 2026

HTTP 401 Unauthorized — The request requires authentication, which is missing or invalid.

Key points

  • Despite the name, it actually means "unauthenticated" — the client must authenticate to get a response
  • Should be paired with a WWW-Authenticate header describing how to authenticate
  • Distinct from 403, which means the client is identified but simply not permitted
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