Lumarc DevTools

JSON Tools

JSON Validator

Check whether JSON is valid and see clear syntax errors before using it in code.

Processed locally — your data never leaves this browser. Input: JSON text Output: Validation result
JSON text

Processed locally — your data never leaves this browser.

Validation result

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Example input and output

Valid object

{"valid":true}
Valid JSON

How to use JSON Validator

Paste or enter your json text, adjust any options, then run the tool. The result appears in the output panel where you can copy or download it.

Related guides

What this tool does

The JSON Validator parses JSON text and reports whether it can be safely read by standards-compliant JSON parsers. It is free to use and designed for technical workflows where pasted data should stay private.

Common use cases

  • Check pasted payloads before deployment
  • Debug API fixtures
  • Confirm configuration syntax

Privacy and security

Processed locally — your data never leaves this browser. Lumarc DevTools does not include a backend, account system or hidden analytics in this initial release.

Limitations

  • Schema validation is not included in this first release.

Frequently asked questions

What JSON standard is used?

The browser JSON parser is used, so strict JSON syntax is required.