Noviilo

JSON Validator

Runs locally

Paste JSON to instantly check whether it's syntactically valid, with an approximate location for any error found.

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Result

Enter JSON above to validate it.

Your data is processed locally in your browser and is not uploaded.

Learn more about this tool⌄

How it works

Validation uses the browser's native JSON.parse and reports any parsing error.

Common use cases

  • Verifying hand-written JSON before deploying config
  • Debugging API payloads
  • Teaching JSON syntax

Frequently asked questions

Does this check my JSON against a schema?
No, this checks syntax only, not structure against a schema.

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