How to use this tool
- Paste the JSON instance first and its JSON Schema in the second editor.
- Run Validate against schema and inspect the first bounded failure or success state.
- Review the result and diagnostics before copying or downloading.
Private by default
JSON Schema Instance Validator
Check types, required fields, properties, arrays, enums, bounds, and local references in the browser.
Your data stays in this browser
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Your data stays in this browserInstantNo server round trips
PrivateBrowser-side processing
AuditableDocumented semantics
PortableCorrectly typed downloads
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JSON Schema Validator: How to use this tool
Validate a JSON instance against a local Draft 2020-12 schema without fetching remote references.
Check types, required fields, properties, arrays, enums, bounds, and local references in the browser.
Open guide and examples
Example to try
Input JSON
{"name":"Ada","age":36,"active":true}JSON Schema
{"$schema":"https://json-schema.org/draft/2020-12/schema","type":"object","required":["name","age"],"properties":{"name":{"type":"string"},"age":{"type":"integer","minimum":0},"active":{"type":"boolean"}},"additionalProperties":false}Result
The JSON instance satisfies the supported safe Draft 2020-12 constraints.
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Frequently asked questions
Is my data sent to a server?
No. The engine runs in your browser and applies local resource limits.
What happens with invalid input?
The tool reports a diagnostic and does not keep stale output.
What does JSON Schema Validator produce?
It reports whether the instance satisfies the supported Draft 2020-12 constraints.
What limitation applies to JSON Schema Validator?
Remote references, regex pattern keywords, and format assertions are not executed.