HTTP
422 Unprocessable Content
The server understands the content type and syntax, but was unable to process the contained instructions. Common in API validation errors.
When You See This Code
When form validation fails — correct syntax but invalid data (e.g., email format wrong, date in the past).
How to Fix
Check the response body for specific validation errors and correct the input data.
Specification
View RFC / Specification →Related Codes
Comparisons
Guides
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HTTP Fundamentals
HTTP Redirects: 301 vs 302 vs 307 vs 308
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HTTP Caching: Cache-Control, ETags, and 304 Responses
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Debugging Timeout Errors: 408 and 504
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Complete Guide to HTTP Methods: GET, POST, PUT, PATCH, DELETE
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API Design
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Designing Consistent API Error Responses
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