API Response Formatter

Master API response handling with our comprehensive formatter. Auto-detect JSON and XML formats instantly, get beautiful syntax highlighting for easy readability, validate responses against schemas, and generate mock data for testing. Includes error detection, indentation controls, format conversion, and one-click copy. Perfect for API developers, QA engineers, and backend developers debugging and testing integrations.

Auto-detect Format Syntax Highlighting Schema Validation Mock Generator Format Conversion

Quick Examples

JSON_RESPONSE: Parse REST API responses with validation and error detection
XML_SUPPORT: Auto-detect and format SOAP/XML responses with schema check
MOCK_DATA: Generate realistic mock responses for API testing scenarios

API Response Input

Options

Indentation

Syntax Highlighting Line Numbers

Validation

JSON

Response Statistics

Format

—

Size

—

Lines

—

Keys/Tags

—

Schema Validation

JSON Schema (JSON Schema Draft-7)

Mock Data Generator

Data Type

Number of Items

Help & Related Tools

Everything you need to know

FAQ Frequently Asked Questions

What formats does the API formatter support?

Supports JSON and XML formats with auto-detection. Features include syntax highlighting, pretty-printing, minification, schema validation, error detection with line numbers, and format conversion (JSON to XML and vice versa).

How do I validate API responses?

Paste or upload your API response (JSON/XML). The tool auto-detects format, pretty-prints, and validates syntax. Use schema validation to check against custom schemas. Errors are highlighted with line numbers for quick debugging.

Can I generate mock API data?

Yes! The mock data generator creates realistic sample responses. Customize data types, array lengths, and field names. Perfect for testing APIs before integration or creating documentation examples.

What file sizes are supported?

The tool handles up to 10MB of API response data. For optimal performance with syntax highlighting, files under 5MB are recommended. All processing happens client-side in your browser.

Does it support schema validation?

Yes! Validate JSON against JSON Schema (draft-7) and XML against XSD schemas. Paste your schema to validate responses. Errors are detailed with location and issue descriptions.