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status code

The three-digit number at the start of an HTTP response saying how it went, like 200 OK or 404 Not Found.

A status code classifies a response: 2xx success, 3xx redirection, 4xx client error (400, 401, 404, 429), 5xx server error.

Examples

  • Posting a reading returns 201 Created; asking for a path that doesn't exist returns 404 Not Found.

  • 429 Too Many Requests and 503 Service Unavailable tell a sensor to slow down or try later.

See also

HTTP method
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