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503 Service Unavailable

The 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. Note that together with this response, a user-friendly page explaining the problem should be sent. This responses 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.

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 should usually not be cached.

Status

503 Service Unavailable

Specifications

Specification Title
RFC 7231, section 6.6.4: 503 Service Unavailable Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

Browser compatibility

FeatureChromeFirefoxEdgeInternet ExplorerOperaSafari
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)
FeatureAndroidChrome for AndroidEdge mobileFirefox for AndroidIE mobileOpera AndroidiOS Safari
Basic Support(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)(Yes)

See also

Document Tags and Contributors

 Contributors to this page: fscholz
 Last updated by: fscholz,