Local in your browserData

Format and validate JSON

Validate structure, format it clearly, and understand syntax errors at the exact position.

Purpose and limits

What this tool does

Validate JSON locally, format it with two or four spaces or tabs, and minify it when needed.

Input
A JSON string up to 1,000,000 characters.
Result
Validated, formatted or minified JSON, or a clear error message.

How to use it

  • Paste JSON, choose indentation, then select Format or Minify.
  • Copy the result explicitly when it is ready.

Limitations

  • Input is limited to 1,000,000 characters to keep the browser responsive.
  • Comments and trailing commas are not valid JSON and are reported as errors.