Paste data and schema
Both panels must contain valid JSON before schema validation can begin.
JSON tools
JSON Schema Validator
Validate JSON against a schema
The result will appear here after you run the tool.
Press Ctrl or Command and Enter to run the tool.
About this tool
About this tool
JSON Schema Validator checks JSON data against a supplied JSON Schema by validating required fields, types, properties, array items, and enum rules locally in the browser. Error messages pinpoint the failing path and rule for quick correction.
Paste JSON data and a JSON Schema to check required fields, core data types, object properties, array items, enum values, and additional property rules.
Built for daily work
- Validate webhook requests against a contract.
- Test sample API responses during development.
- Check configuration files before deployment.
- Review generated data before import.
How to use this tool
How to use this tool
Run validation
The validator checks supported keywords and records the exact data path for each failure.
Correct and repeat
Fix the data or schema, then validate again until the result matches the intended contract.
Key features
Key features
Path-annotated error list
Each validation failure includes the JSONPath to the offending property or array index so you can locate it in the data document.
Core structural keywords
Checks type, required, properties, items, enum, const, minimum, maximum, and additionalProperties. Format keywords such as email and URI are not yet enforced.
Separate data and schema inputs
Load a JSON data document in the left panel and a schema in the right, each with its own file upload and example.
Validation stays in the browser
Neither the data instance nor the schema is sent to any server during checking.
Practical use cases
Practical use cases
- Validate webhook requests against a contract.
- Test sample API responses during development.
- Check configuration files before deployment.
- Review generated data before import.
Private by default
For local tools, input is processed in your browser and is not sent to application analytics.
Data processing noticeTechnical details
Technical details
Supported typesobject, array, string, number, integer, boolean, null
Supported keywordstype, required, properties, items, enum, additionalProperties
Error pathsJSONPath style
ProcessingLocal browser processing
Limitations and important notes
Limitations and important notes
- This is not a complete implementation of every draft 2020-12 keyword.
- Conditional, reference, composition, and advanced numeric or string constraints are not fully supported.
- Use a standards compliant server library for critical production enforcement.
Frequently asked questions
Frequently asked questions
No. The current local validator focuses on common structural keywords. Review the limitations and use a full standards implementation for complex production contracts.
Yes. Use JSON Schema Generator to create a starting point, then edit and validate it here.
The current release does not enforce every format such as email, URI, hostname, or date-time.
Related guides and solutions
Related guides and solutions
How to validate JSON with JSON Schema
A practical introduction to generating a starting schema, strengthening constraints, and interpreting validation errors.
Learn moreJSON syntax and data type reference
A compact technical reference for writing and validating strict JSON that can be opened in standards-compliant parsers.
Learn moreCommon JSON syntax errors and how to fix them
Valid JSON requires double quoted property names and strings, balanced brackets, supported values, correct escaping, and no trailing commas or comments.
Learn moreRelated tools
Related tools
JSON tools
JSON Schema Generator
Infer a JSON Schema from sample data with nested properties, required fields, arrays, and detected types.
Open toolJSON tools
JSON Formatter and Validator
Format, validate, inspect, search, and analyze JSON in code, tree, table, schema, and statistics views.
Open toolJSON tools
JSON Diff Checker
Compare two JSON values and list additions, removals, type changes, and value changes by path.
Open tool