Yes, completely free with no signup required.

Does my data leave my device?

No. All validation happens locally in your browser — nothing is sent to a server.

Does it work on mobile?

Yes. The tool is mobile-first and works on any modern browser.

Validate a JSON document against a JSON Schema — checks required fields, types, and enum values.

100% in your browser. Your file never leaves your device.

JSON document

JSON Schema

Paste the JSON document above, the schema below, then click Validate.

Paste your JSON document in the top input.
Paste your JSON Schema in the schema field.
Click "Validate" — errors are listed with the path and message, or you see a "Valid" result.

Is this tool free?: Yes, completely free with no signup required.
Does my data leave my device?: No. All validation happens locally in your browser — nothing is sent to a server.
Does it work on mobile?: Yes. The tool is mobile-first and works on any modern browser.