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JSON Schema Validator
Validate JSON against a schema (Draft-07 or 2020-12) and generate a schema from sample data.
Free, no uploads, no sign-up. Runs 100% in your browser.
How JSON Schema Validator works
Validation uses Ajv with the standard formats (email, date, uri and more). Every error is listed with the path to the bad value. The generator looks at your data and writes a matching schema with types, required keys and detected formats.
Input: JSON. Output: JSON Schema.
How to use JSON Schema Validator
- Open JSON Schema Validator and add your file or input.
- Pick the options you need. Everything runs on your device.
- Press the main button and download the result.
Tips
- Nothing is uploaded. Your files stay in this browser tab.
JSON Schema Validator FAQ
- Are my files uploaded?
- No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
- Is it free? Are there limits or watermarks?
- Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
- Does it work offline?
- Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.
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