JSON Schema Validator
Validate JSON data against a JSON Schema (Draft-07). Check types, required fields, formats, patterns, enums, and nested constraints — entirely in your browser.
Supported Schema Keywords
| Category | Keywords |
|---|---|
| General | type, enum, const, $ref |
| String | minLength, maxLength, pattern, format (email, uri, date-time, date, time, ipv4, ipv6, uuid) |
| Number | minimum, maximum, exclusiveMinimum, exclusiveMaximum, multipleOf |
| Array | items, minItems, maxItems, uniqueItems, contains |
| Object | properties, required, additionalProperties, patternProperties, minProperties, maxProperties, dependencies |
| Combinators | allOf, anyOf, oneOf, not, if/then/else |
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Frequently Asked Questions
What is JSON Schema?
JSON Schema is a vocabulary that allows you to annotate and validate JSON documents. It defines the shape of your data — types, required fields, string patterns, number ranges, and more. It's widely used for API request/response validation, configuration files, and form generation.
Which JSON Schema draft does this support?
This validator implements a practical subset of JSON Schema Draft-07, covering the most commonly used keywords: type, properties, required, enum, const, format validations, array constraints, combinators (allOf, anyOf, oneOf, not), conditionals (if/then/else), $ref, and more.
What formats are validated?
When format validation is enabled, this tool checks: email, uri, date-time (ISO 8601), date, time, ipv4, ipv6, and uuid. Format validation follows the specification's recommendation of basic structural checks.
Is my data safe?
Yes. All validation happens entirely in your browser using JavaScript. No data is sent to any server. Your schemas and data never leave your machine.