JSON Schema Validator

Ensure your JSON data strictly adheres to a predefined JSON Schema structure.

Schema Match

✓ Data is valid against the schema.

JSON Data

{
  "name": "Ada Lovelace",
  "born": 1815
}

{
  "name": "Ada Lovelace",
  "born": 1815
}

JSON Schema

{
  "type": "object",
  "required": [
    "name",
    "born"
  ],
  "properties": {
    "name": {
      "type": "string"
    },
    "born": {
      "type": "number"
    }
  }
}

{
  "type": "object",
  "required": [
    "name",
    "born"
  ],
  "properties": {
    "name": {
      "type": "string"
    },
    "born": {
      "type": "number"
    }
  }
}

JSON Schema Validator Online

Building a robust API requires strict data validation. Our free online JSON Schema Validator lets you instantly verify whether your JSON payloads conform to a predefined structural blueprint. Catch missing fields, incorrect data types, and constraint violations before they break your backend.

100% Client-Side Validation: Both your JSON Schema and your payload are parsed securely within your browser. No sensitive API configurations are ever transmitted to our servers.

Core Features

Strict Type CheckingEnsure that integers aren't passed as strings, arrays contain the correct number of items, and nested objects match your exact specification.
Clear Error ReportingStop guessing why validation failed. Our tool provides precise error messages detailing exactly which property failed and which constraint was violated.
Draft Standard SupportFully compatible with modern JSON Schema drafts, supporting complex keywords like anyOf, allOf, and pattern matching.

Example: Catching Schema Errors

JSON Schema

{
  "type": "object",
  "required": ["age"],
  "properties": {
    "age": {
      "type": "integer",
      "minimum": 18
    }
  }
}

JSON Payload

{
  "name": "Bob",
  "age": 16
}

Validation Error

Error: instance.age must be >= 18
Path: $.age
Value: 16

Frequently Asked Questions

What is the difference between a Validator and a Schema Validator?

A standard JSON Validator only checks for syntax (e.g., missing commas, unescaped quotes). A JSON Schema Validator takes a perfectly valid JSON file and checks its content against a blueprint—ensuring that required fields exist, integers aren't passed as strings, and specific data formats are strictly followed.

Is my schema data kept private?

Yes, entirely. The schema validation engine runs locally in your web browser. Neither your schema design nor your payload data is ever uploaded to a server.