What causes a 422 error?

Common causes of a 422 error include missing required fields, invalid or malformed data (such as an improperly formatted email), business rule violations, or authorization issues that prevent processing.

How do I fix a 422 status code?

To fix a 422 status code, check that your request includes all required fields, uses valid formats, and follows business rules. Validate data on both the client and server, and look at the error response for details on what went wrong.

What is an example of a 422 error?

A 422 error can occur when submitting a form with missing or invalid fields. For example, a POST request that includes an empty 'name' and an invalid 'email' will return a 422 response indicating that the input cannot be processed.

Where might I encounter a 422 status code?

422 errors are commonly seen in web APIs such as GitHub, Stripe, or Shopify, and in frameworks that enforce data validation like Laravel, Django, or Ruby on Rails.

What Is a 422 Status Code?

Q: What is a 422 status code?

A 422 Unprocessable Entity error means the server understood the request, but could not process it due to semantic issues. The request is well-formed, but the data fails validation or business logic rules.

A 422 Unprocessable Entity error means the server understood the request, but could not process it due to semantic issues. The structure is valid, but something about the data does not meet requirements.

Common causes include:

Missing required fields
Malformed input (e.g., an email missing the @)
Business rule violations (e.g., trying to book a past date)

422 Code References

Rails: :unprocessable_entity
Symfony: Response::HTTP_UNPROCESSABLE_ENTITY
.NET: HttpStatusCode.UnprocessableEntity
Rust: http::StatusCode::UNPROCESSABLE_ENTITY
Go: http.StatusUnprocessableEntity
Python 3.5+: http.HTTPStatus.UNPROCESSABLE_ENTITY
Apache HC: org.apache.hc.core5.http.HttpStatus.SC_UNPROCESSABLE_ENTITY
Angular: @angular/common/http/HttpStatusCode.UnprocessableEntity

422 Status Code Example

Here is a typical request and response scenario that triggers a 422 error:

Request

POST /api/users HTTP/1.1
Host: example.com
Content-Type: application/json

{
  "name": "",
  "email": "example.com"
}

Response

HTTP/1.1 422 Unprocessable Entity
Content-Type: application/json

{
  "error": "Unprocessable Entity",
  "message": "Validation failed",
  "details": [
    {
      "field": "name",
      "message": "Name is required"
    },
    {
      "field": "email",
      "message": "Invalid email address"
    }
  ]
}

This error occurs because the submitted JSON payload does not meet validation rules. The server returns a 422 with helpful messages so the client can fix and resubmit the request.

What Causes a 422 Status Code?

Validation errors: Input fails validation rules, such as a required field being empty or incorrectly formatted.
Business logic errors: The request violates a rule, such as using a duplicate email or an invalid state transition.
Authorization issues: The action may not be permitted for the current user, depending on the endpoint logic.
Data conflicts: The request may conflict with existing data or application constraints.

How to Fix a 422 Status Code

Review the request payload: Confirm it includes all required fields and that data is well-formed.
Validate on both client and server: Use front-end validation where possible and ensure robust server-side validation.
Return clear error messages: Help users and developers identify what went wrong and how to fix it.
Use debugging tools: Logs, dev tools, and HTTP interceptors can help trace bad requests.