503.md

set	code	title	references
5	503	Service Unavailable	Rails HTTP Status Symbol Go HTTP Status Constant Symfony HTTP Status Constant Python2 HTTP Status Constant Python3+ HTTP Status Constant Python3.5+ HTTP Status Constant :service_unavailable http.StatusServiceUnavailable Response::HTTP_SERVICE_UNAVAILABLE httplib.SERVICE_UNAVAILABLE http.client.SERVICE_UNAVAILABLE http.HTTPStatus.SERVICE_UNAVAILABLE

The server is currently unable to handle the request due to a temporary overload or scheduled maintenance, which will likely be alleviated after some delay.

The server MAY send a Retry-After header field¹ to suggest an appropriate amount of time for the client to wait before retrying the request.

Note: The existence of the 503 status code does not imply that a server has to use it when becoming overloaded. Some servers might simply refuse the connection.

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• ¹ Retry-After RFC7231 Section 7.1.3
• Source: RFC7231 Section 6.6.4