JSON Tools

JSON Schema Validator

Validate your JSON data against a JSON Schema. Ensure data integrity, catch errors early, and enforce structure.

Validate JSON Against Schema

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Pro Tip: JSON Schema helps catch data errors before they cause problems in production. All validation happens in your browser - your data is 100% private and never sent to any server.

What is JSON Schema?

JSON Schema is a vocabulary that allows you to annotate and validate JSON documents. It describes the structure, data types, and constraints of your JSON data.

By validating JSON against a schema, you can ensure data consistency, catch errors before they cause problems, and document your API contracts clearly.

How to Validate JSON with Schema

  1. Paste your JSON Schema in the left editor (defines the structure)
  2. Paste your JSON data in the right editor (the data to validate)
  3. Click "Validate" to check if JSON matches the schema
  4. Review results - see if valid or get detailed error messages
  5. Fix errors and validate again until your data is correct

Common Use Cases

🔌 API Validation

Validate API request/response payloads against defined schemas

⚙️ Configuration Files

Ensure config files have the correct structure and data types

📝 Form Validation

Validate user input data against predefined schemas

🧪 Testing

Validate test data and mock responses in automated tests

Supported Schema Features

✓Type validation (string, number, boolean, array, object, null)
✓Required properties
✓String patterns (regex)
✓Number ranges (min, max)
✓Array validation (items, length)
✓Enum values
✓Nested objects
✓Additional properties

Frequently Asked Questions

What JSON Schema versions are supported?

This validator supports JSON Schema Draft 7, Draft 2019-09, and Draft 2020-12 (latest).

Is my data secure?

Yes! All validation happens in your browser. Your JSON data and schemas never leave your device.

What happens if validation fails?

You'll get detailed error messages showing exactly what's wrong, which field failed, and what was expected vs. what was found.

Can I validate complex nested structures?

Absolutely! JSON Schema supports deeply nested objects and arrays with full validation at every level.