Free Online JSON Schema Validator
Validate your JSON data against a JSON Schema. Supports draft-04, draft-07, and 2020-12 schemas.
schema JSON Schema
data_object JSON Data
Click Validate to check JSON data against the schema.
Key Features
Schema Compliance
Validate JSON data against any JSON Schema draft-04, draft-07, or 2020-12.
Detailed Error Messages
Get precise error messages with the exact path to each validation failure.
Instant Feedback
Validation runs instantly in your browser with no server roundtrips.
Privacy Protected
Your schema and data never leave your browser. Zero data upload.
Frequently Asked Questions
Getting Started
What is JSON Schema validation?
JSON Schema validation checks whether a JSON document conforms to a predefined schema structure, including required fields, data types, and value constraints.
Which schema drafts are supported?
The validator supports draft-04, draft-07, and 2020-12 schema formats automatically.
Features & Usage
Can I validate large JSON files?
The tool handles files up to a few MB. Performance depends on the complexity of both the schema and the data.
Is my data safe?
Yes. All validation runs locally in your browser. Your data never leaves your device.
How accurate is the validation?
The tool performs structural validation including type checking, required fields, and array item validation. Some advanced constraints like pattern matching and numeric ranges have basic support.
Troubleshooting
What happens if my schema or data is invalid JSON?
The tool will display a parse error message. Ensure both the schema and data are valid JSON before validating.
Can I use this tool offline?
Yes. Once the page is loaded, all functionality works offline thanks to local processing.
What is the difference between JSON validation and JSON Schema validation?
JSON validation checks if a string is valid JSON syntax. JSON Schema validation checks if valid JSON data conforms to a predefined structure and constraints defined in a JSON Schema document.