JSON Validator

Validate, format or minify JSON in your browser

About JSON Validator

Validate JSON and instantly see syntax errors, or format and minify valid JSON. Runs entirely in your browser.

How to use the json validator

  1. Paste your JSON.
  2. Click Validate & Format or Minify.
  3. See errors or the cleaned output.
  4. Copy the result.

Frequently asked questions

What errors does it catch?

It reports the exact JSON.parse error message, such as an unexpected token or missing comma, so you can fix invalid JSON quickly.

Are my files uploaded to a server?

No. Everything runs locally in your browser, so your files and text never leave your device.

Is this tool free?

Yes, completely free with no signup, watermarks or limits.

Related tools