HTTP Error Response Generator

Developer

Generate standardized HTTP error responses for API development and testing.

Error Configuration

Status Code Reference

4xx - Client Errors
5xx - Server Errors

400: Bad syntax/validation

401: Authentication required

403: Forbidden (no permission)

404: Resource not found

422: Unprocessable entity

429: Rate limit exceeded

500: Internal server error

503: Service unavailable

400Bad Request
{
  "errors": [
    {
      "status": "400",
      "title": "Bad Request",
      "detail": "The request was invalid or cannot be served."
    }
  ],
  "meta": {
    "timestamp": "2026-03-24T20:20:58.347Z"
  }
}
Response Headers
HTTP/1.1 400 Bad Request
Content-Type: application/json
Date: Tue, 24 Mar 2026 20:20:58 GMT
X-Request-Id: 4a3e9d33-92e4-4890-9348-7ae2b2602506
Cache-Control: no-store

Usage Examples

Express.js

res.status(400).json({"errors":[{"status":"400","title":"Bad Request","detail":"The request was invalid or cannot be served."}],"meta":{"timestamp":"2026-03-24T20:20:58.347Z"}});

Fetch API (Testing)

throw new Response(JSON.stringify(error), { status: 400 });

cURL Test

curl -X GET http://api.example.com/resource -H "Accept: application/json"

Common Error Scenarios

What is This Tool?

An HTTP error response generator creates properly formatted error response payloads for REST APIs. Generate error responses following RFC 7807 (Problem Details), custom error formats, and platform-specific conventions with correct HTTP status codes and error metadata.

Consistent error responses are critical for API usability. RFC 7807 defines a standard error format with type, title, status, detail, and instance fields. Many teams use custom formats with error codes, validation details, and request IDs. This tool generates both standard and custom error payloads.

Common Use Cases

API Design

Establish consistent error response formats during API design, generating examples for documentation and client SDK development.

Error Handling Development

Generate diverse error scenarios (4xx, 5xx) with proper formats for testing error handling and display in frontend applications.

Testing

Create error response fixtures for testing retry logic, error boundary components, and graceful degradation patterns.

Documentation

Generate example error responses for API documentation showing what clients should expect for each failure mode.

Frequently Asked Questions

What is RFC 7807?

An IETF standard for HTTP error responses. It defines a JSON format with type (URI), title, status, detail, and instance fields for machine-readable error details.

Which status codes are covered?

All standard HTTP error codes: 400 Bad Request, 401 Unauthorized, 403 Forbidden, 404 Not Found, 409 Conflict, 422 Unprocessable, 429 Rate Limited, 500 Internal Error, and more.

Can I add validation errors?

Yes. Generate error responses with field-level validation details, including field name, error code, and human-readable messages.