JSON Schema Validator
Validate JSON data against a JSON Schema. Instantly check structure, types, and constraints with detailed error messages.
Related JSON Tools
What Is a JSON Schema Validator?
A JSON Schema Validator checks whether a JSON document conforms to a JSON Schema definition. JSON Schema is a vocabulary that allows you to annotate and validate JSON documents, ensuring data has the correct structure, types, and constraints before it is processed by your application.
How to Use
- Paste your JSON data into the left textarea.
- Paste your JSON Schema into the right textarea.
- Click "Validate" to check the data against the schema.
- Review the validation result — green means valid, red lists each error with its path.
Supported Keywords
- type — validates the data type (string, number, integer, boolean, object, array, null)
- required — ensures specified properties are present in an object
- properties — validates nested object properties against sub-schemas
- minLength / maxLength — enforces string length constraints
- minimum / maximum — enforces numeric range constraints
- enum — restricts a value to a fixed set of allowed values
- pattern — validates strings against a regular expression
- items — validates each element of an array against a sub-schema
- additionalProperties — controls whether extra object keys are allowed
FAQ
Is my data sent to a server?
No. All validation runs entirely in your browser. Your JSON data and schema never leave your machine.
Which JSON Schema draft is supported?
This tool implements the most commonly used keywords from JSON Schema Draft 7 and later drafts. It covers type, required, properties, string/number constraints, enum, pattern, items, and additionalProperties.
What do the error paths mean?
Each error shows a dot-notation path like $.address.zip indicating exactly which field failed validation, making it easy to locate and fix the issue in your data.