JSON Schema is a vocabulary that lets you annotate and validate JSON documents. It defines the structure, data types, and constraints a JSON document must meet. The draft-07 specification is the most widely supported version and is used by tools like Swagger/OpenAPI, MongoDB, and Kubernetes.

Which JSON Schema draft does this tool support?

This tool supports JSON Schema draft-07, the most widely used version. It covers keywords like $ref, allOf, anyOf, oneOf, not, if/then/else, as well as standard format validators (date, email, uri, uuid, ipv4, ipv6).

Is my data sent to any server?

No. All validation runs entirely in your browser using the AJV library compiled into the page. Your JSON schema and data never leave your device.

What do the error paths mean?

Errors use JSON Pointer notation (RFC 6901). For example, /user/email means the 'email' property inside the 'user' object. /items/0/name means the 'name' property of the first element in the 'items' array.

Can I use $ref to reference definitions?

Yes. You can use $ref with $defs (or definitions for draft-07 compatibility) within the same schema document. External URL references are not supported since all validation runs offline in the browser.

How do I validate an array of objects?

Use the 'items' keyword in your schema. For example: { "type": "array", "items": { "type": "object", "required": ["id"], "properties": { "id": { "type": "integer" } } } }

100% Client-Side — No Data Leaves Your Browser

Validate JSON Against
Any Schema Instantly

Paste your JSON Schema and JSON data, then validate in real-time. Get precise error messages with JSON Pointer paths so you can fix issues fast.

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Real-Time Validation

Validates automatically as you type with instant feedback — no button press needed.

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Precise Error Paths

Each error shows the exact JSON Pointer path and the schema rule that failed.

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100% Private

All validation runs in your browser. Your schemas and data never touch a server.

SchemaJSON Schema (draft-7)

DataJSON to Validate

Enter schema and data above

Common JSON Schema keywords reference

required["field1", "field2"] — required properties

properties{ "name": { "type": "string" } } — object properties

items{ "type": "string" } — array item schema

enum["a", "b", "c"] — allowed values

minimum / maximumnumber bounds (exclusiveMinimum / exclusiveMaximum)

minLength / maxLengthstring length bounds

pattern"^[A-Z]+" — regex pattern for strings

format"email" | "uri" | "date" | "uuid" | "ipv4" | "ipv6"

allOf / anyOf / oneOfcombine multiple schemas

if / then / elseconditional schema application

$ref / $defsreference reusable schema definitions

Frequently Asked Questions

Everything you need to know about JSON Schema Validator.