The HyperText Transfer Protocol (HTTP)
503 Service Unavailable server error response code indicates that the server is not ready to handle the request.
Common causes are a server that is down for maintenance or that is overloaded. This response should be used for temporary conditions and the
Retry-After HTTP header should, if possible, contain the estimated time for the recovery of the service.
Note: together with this response, a user-friendly page explaining the problem should be sent.
Caching-related headers that are sent along with this response should be taken care of, as a 503 status is often a temporary condition and responses shouldn't usually be cached.
503 Service Unavailable
|RFC 7231, section 6.6.4: 503 Service Unavailable||Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content|
The information shown below has been pulled from MDN's GitHub (https://github.com/mdn/browser-compat-data).
|Android webview||Chrome for Android||Edge Mobile||Firefox for Android||Opera for Android||iOS Safari||Samsung Internet|
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