VitaliWeb Tools

JSON Formatter & Validator

Readable JSON, precise validation. Your numbers stay intact.

Processed on your deviceFree · No account needed
0 / 100,000 input code units

Large numbers retain their exact digits. JSON is validated, never executed.

How to use it

  1. Paste a JSON document.
  2. Choose indentation or compact output, then format and validate.

{"id":9007199254740993,"ok":true} keeps the exact ID when formatted.

Details & limits

100,000 characters; nesting limited to 100 levels. Number spelling, string values and duplicate keys are preserved.

Will large numbers lose precision?

No. The formatter validates JSON syntax without converting numeric tokens into JavaScript numbers. Original numeric spelling and duplicate keys are retained. A valid document is not a schema validation or a guarantee that duplicate keys are meaningful.