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📐 JSON Schema Validator

Validate JSON against a JSON Schema. Type mismatches, missing required fields, enum violations, pattern mismatches — all shown with location. Draft 7 / 2019-09 / 2020-12.

✅ 100% free, no signup, runs entirely in your browser

Result will appear here.

🔗 Related Tools

📖 How to Use

  1. 1
    Enter your JSON Schema
    Paste your JSON Schema (Draft 7 / 2019-09 / 2020-12) into the left textarea. Click Sample to load a working example.
  2. 2
    Enter the JSON data to validate
    Paste the JSON data you want to validate into the right textarea. Validation runs automatically whenever either side is edited.
  3. 3
    Review errors and fix them
    If errors exist, they are listed with the field path, message, and params. Use them to fix either your JSON data or the schema.

❓ FAQ

Which Draft versions are supported?
This tool uses Ajv 8 and supports JSON Schema Draft 7, 2019-09, and 2020-12. The version is auto-detected from the $schema field.
Does format validation (email, date, etc.) work?
This tool treats format as an annotation by default and does not fail on format violations. Strict format validation requires an extension like ajv-formats.
What is JSON Schema?
JSON Schema is a specification for describing the structure, types, and constraints of JSON data. It is widely used for API request/response validation, config file validation, and form validation.