Free online JSON & YAML validator & compare tool
Our JSON & YAML validator online helps developers quickly validate JSON and YAML syntax and compare files. This free JSON & YAML validation tool provides instant error detection with precise line highlighting for both formats.
About Unifieddiff JSON & YAML validator & comparator
Our free online JSON and YAML validator, comparator and parser tool helps developers quickly validate syntax, identify errors, parse JSON strings, and compare JSON and YAML files or text. The JSON parser converts between different formats including JavaScript objects and Python dictionaries. Perfect for debugging, API development, configuration management, and data validation tasks across multiple formats.
Key features
- JSON & YAML syntax validation: Instantly validate both JSON and YAML with detailed error reporting and line highlighting.
- JSON & YAML comparison: Compare two JSON or YAML files or text with visual diff highlighting.
- JSON parser: Parse JSON strings to objects and convert between JavaScript, Python and standard JSON formats.
- Dual format support: Switch seamlessly between JSON and YAML tools with consistent interface.
- Error detection: Precise error location with line and column information for both formats.
- File upload support: Upload and compare JSON (.json) and YAML (.yaml, .yml) files directly from your device.
- Free & secure: No data is stored on our servers.
How to use
- Choose format: Select JSON or YAML tools using the format selector at the top.
- To validate: Paste your JSON or YAML content into the validator and click the "Validate" button to check for syntax errors.
- To compare text: Use the "Diff tool" tab to paste two JSON or YAML snippets and see the differences.
- To compare files: Upload two JSON or YAML files using the "Compare files" tab to find discrepancies.
- To parse JSON: Use the "JSON parser" tab to convert JSON strings to objects or format JSON with multiple output options.
Supported formats
JSON: Complete JSON validation and comparison including arrays, objects, strings, numbers, booleans, and null values.
YAML: Full YAML 1.2 support including scalars, sequences, mappings, multi-line strings, and complex nested structures.
Unifieddiff JSON & YAML validator & comparator - A free online tool for developers. No registration required.
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