JSON Schema Validator
JSON Schema is a vocabulary for validating JSON data structure. A schema defines types (string, number, integer, boolean, array, object, null), required fields, constraints (minLength, maxLength, minimum, maximum, pattern), and formats (email, URI, date). To validate: parse both JSON and schema, then check every constraint recursively. Errors report the JSONPath location (e.g., $.users[0].email) and what failed.
Validate JSON data against a JSON Schema. Checks types, required fields, string patterns, numeric ranges, array constraints, and more. Supports format validation (email, URI, date). Shows all errors with JSONPath locations. Presets for common schemas: user objects, product arrays, config files, API responses.
Presets
JSON Data
JSON Schema
Validation Result
JSON data matches the schema.
Supported Validations
| Keyword | Applies To | Description |
|---|---|---|
| type | any | string, number, integer, boolean, array, object, null |
| required | object | List of required property names |
| properties | object | Schema for each property |
| additionalProperties | object | false to disallow extra keys, or schema for extra keys |
| minLength / maxLength | string | String length constraints |
| pattern | string | Regex pattern the string must match |
| format | string | email, uri, date, date-time |
| minimum / maximum | number | Numeric range (inclusive) |
| exclusiveMinimum / exclusiveMaximum | number | Numeric range (exclusive) |
| multipleOf | number | Value must be divisible by this |
| minItems / maxItems | array | Array length constraints |
| uniqueItems | array | true to require distinct elements |
| items | array | Schema applied to each array element |
| enum | any | List of allowed values |
| const | any | Single allowed value |
How to Use
- 1
Enter your JSON data
Paste the JSON you want to validate in the left panel. Or click a preset (User Object, Product Array, Config File, API Response) to load sample data.
- 2
Enter or paste a JSON Schema
Paste your JSON Schema in the right panel. The schema defines required fields, types, constraints, and formats that the JSON must match.
- 3
View validation results
Results appear instantly. Green means valid. Red shows each error with its JSONPath location and a description of what failed.
- 4
Copy the results
Click Copy to copy the validation output. Fix errors in your JSON based on the reported paths and re-validate.