JSON Schema validator
Paste a JSON Schema and a JSON instance — validate in the browser with Ajv. Schema compile errors and per-field validation errors shown separately.
Your data never leaves the browser — no upload, no server.
Validation errors
| Instance path | Keyword | Message |
|---|---|---|
About this tool
Uses Ajv with strict: false and validateFormats: false — format keywords are not enforced (no ajv-formats addon). Good for quick schema checks during API design.
Supports draft 2020-12 schemas when bundled with Ajv 8. For runtime TypeScript validation, see Zod or the JSON to Zod converter.
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