JSON Formatter

Validate, pretty-print and inspect JSON

Use this when you need a fast, accurate result — no sign-up, works entirely in your browser.

JSON Formatter — Validate, pretty-print and inspect JSON
Formatted JSON—
Status—

How to Use

  1. Enter your details into the fields above.
  2. Click the calculate button to get your result instantly.
  3. Use the clear button to start a new calculation.

Example

  • {"a":1,"b":[2,3],"c":{"x":"y"}} with 2-space indent → Pretty-printed valid JSON, status: ✓ Valid JSON
  • {"name":"tools","items":[1,2,3]}, indent 2 spaces → Pretty-printed with 2-space indent; valid JSON

Formula

Parses the input with JSON.parse, then re-serialises with JSON.stringify(value, null, indent) where indent is 1-8 spaces. Returns an error message on invalid JSON.

About JSON Formatter

Validate, pretty-print and inspect JSON. This free online tool gives you fast, accurate results without registration or downloads.

Everything runs locally in your browser, so your data is never uploaded or stored — privacy first.

Frequently Asked Questions

Is this tool free to use? +
Yes, it is completely free with no registration or download required.
Is my data private? +
Yes. Everything is processed locally in your browser. Nothing is uploaded or stored on our servers.
Does it work on mobile? +
Yes, it works on any device — phone, tablet, or desktop.