428

Precondition Required

Description

The origin server requires the request to be conditional. This response is intended to prevent the 'lost update' problem, where a client GETs a resource's state, modifies it, and PUTs it back to the server.

HTTP Status Codes Details

Status Code
428
Status Name
Precondition Required
Class
4xx
Common Usage
No

Common Scenarios

  • Client request errors
  • Authentication issues

Handling Recommendations

  • Validate client input
  • Provide clear error messages

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Fact-checking completed

Verified by: Pavel Volkov
Created:
Last updated:
Information verified against official sources

Official Sources

Internet Engineering Task Force RFCs

Official HTTP status codes specification (RFC 7231)

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Comprehensive HTTP status codes documentation

Authoritative web development documentation

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Internet Assigned Numbers Authority

Official HTTP status code registry

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