400

Bad Request

Description

The server could not understand the request due to invalid syntax. The client should not repeat the request without modifications. This is often caused by malformed request syntax, invalid request message framing, or deceptive request routing.

HTTP Status Codes Details

Status Code
400
Status Name
Bad Request
Class
4xx
Common Usage
Yes

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)

Internet standards organization defining HTTP protocols

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Mozilla Developer Network

Comprehensive HTTP status codes documentation

Authoritative web development documentation

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Internet Assigned Numbers Authority

Official HTTP status code registry

Internet protocol parameters authority

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