Toolnetix

JSON Formatter & Validator

Validate, prettify, minify, and copy JSON with indent and key-sorting options in one fast tool.

All formatting and validation happen in your browser.

JSON input

Formatted output

Formatted JSON will appear here.

Common JSON errors (and how to fix them)

1) Single quotes / unquoted keys

Invalid:

{ 'name': 'Sandeep', active: true }

Fix:

{ "name": "Sandeep", "active": true }

2) Trailing comma

Invalid:

{ "a": 1, }

Fix:

{ "a": 1 }

3) Not JSON at all

Invalid:

<html>...</html>

Fix:

Make sure you paste valid JSON, e.g.:
{ "status": "ok" }

If you’re still stuck, click Validate to see the error location, then fix the first error before moving on.

About this tool

Toolnetix JSON Formatter and Validator helps you validate, prettify, and minify JSON with optional key sorting for consistent output. It is useful for debugging APIs, cleaning payloads, and preparing test fixtures. Everything runs locally in your browser, so your JSON is not uploaded or stored on external servers. Use Format to improve readability, Minify to reduce size, and Validate to catch syntax issues quickly. After cleanup, copy the result and continue with related tools like Base64, URL encode/decode, or JWT decoding. Try next: JSON Formatting guide • JSON vs XML comparison.

How to use

  1. Paste JSON content into the editor.
  2. Choose indent size and optional key sorting.
  3. Use Format or Minify based on your workflow.
  4. Use Validate to check syntax quickly.
  5. Copy formatted output when ready.

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Frequently asked questions