JSON Schema Validator

Validate JSON against JSON Schema Draft 2020-12 with detailed Ajv errors. Everything runs in your browser.

Input JSON

{
  "id": "user_42",
  "email": "alice@example.com",
  "role": "editor",
  "tags": ["billing", "beta"],
  "profile": {
    "displayName": "Alice",
    "timezone": "America/New_York"
  }
}

JSON Schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "id": { "type": "string", "pattern": "^user_[a-z0-9]+$" },
    "email": { "type": "string", "format": "email" },
    "role": { "type": "string", "enum": ["admin", "editor", "viewer"] },
    "tags": {
      "type": "array",
      "items": { "type": "string" },
      "uniqueItems": true
    },
    "profile": {
      "type": "object",
      "properties": {
        "displayName": { "type": "string", "minLength": 1 },
        "timezone": { "type": "string" }
      },
      "required": ["displayName"],
      "additionalProperties": false
    }
  },
  "required": ["id", "email", "role"],
  "additionalProperties": false
}

Draft 2020-12

Supports modern keywords like $defs, prefixItems, dependentRequired, and unevaluatedProperties.

Format Checks

Email, URI, date-time, UUID, IPv4, and IPv6 formats are enabled through ajv-formats.

Private by Default

The validator runs in the browser, so API payloads, configs, and schemas stay on your device.

Frequently Asked Questions

Is an empty JSON Schema {} valid?

Yes. An empty schema object {} is valid and accepts any JSON value. It is equivalent to the boolean schema true for assertion behavior. Use it only when any value is intentionally allowed.

Does this tool upload my JSON?

No. Validation runs client-side in your browser with Ajv. Your JSON and schema are not sent to BytePane servers.

Which JSON Schema draft is supported?

This validator uses Ajv with the Draft 2020-12 entry point. Draft 2020-12 supports prefixItems, $defs, unevaluatedProperties, dependentRequired, and the current format vocabulary model.

Why did my email or URL format fail?

Format checks are enabled with ajv-formats. That means email, uri, date-time, uuid, ipv4, and ipv6 are validated instead of treated as simple annotations.

JSON Schema Validator

Draft 2020-12

Format Checks

Private by Default

Frequently Asked Questions

Is an empty JSON Schema {} valid?

Does this tool upload my JSON?

Which JSON Schema draft is supported?

Why did my email or URL format fail?

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