HTTP 503 Service Unavailable — Meaning

503 Service Unavailable means the server is temporarily unable to handle the request — typically overload or maintenance. Tell clients when to retry via the Retry-After header.

Key facts

Frequently asked questions

What does 503 mean?

The server is temporarily unavailable (overload or maintenance).

Is 503 temporary?

Yes; it signals a transient condition, often with a Retry-After hint.

Related pages

• HTTP 200 OK
• HTTP 301 Moved Permanently
• HTTP 401 Unauthorized
• HTTP 403 Forbidden
• HTTP 404 Not Found
• HTTP 429 Too Many Requests
• HTTP 500 Internal Server Error
• HTTP 502 Bad Gateway

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