DevUtils

JSON Formatter & Validator

Validate, format, and beautify your JSON data.

What is a JSON Formatter & Validator?

JSON (JavaScript Object Notation) is the standard data format for modern APIs. However, minified JSON is unreadable. This JSON Formatter takes raw, messy, or minified JSON strings and beautifies them with proper indentation, while also validating syntax to catch missing commas or quotes.

How to use

  • 1Paste your raw JSON into the input area.
  • 2Click 'Format JSON'.
  • 3If there are syntax errors, a clear error message will appear.
  • 4If valid, the beautified JSON will appear in the output panel.

JSON Formatter guide

Use this JSON formatter to validate pasted JSON and turn compact API responses, configuration files, and payloads into readable, consistently indented data. Formatting happens locally in your browser.

When to use it

  • Inspect a minified API response while debugging a frontend integration.
  • Validate a JSON configuration file before committing it.
  • Make a JSON payload easier to review in a pull request or support ticket.

Format a compact API response

Input

{"user":{"id":42,"role":"admin"}}

Result

{
  "user": {
    "id": 42,
    "role": "admin"
  }
}

Common questions

Does the formatter send my JSON to a server?
No. Formatting and validation run in your browser.
Why is my JSON invalid?
The most common causes are single quotes, trailing commas, unquoted keys, or comments.

Keep building

Related Tools

URL Encoder / Decoder

Safely encode or decode URL components for safe transmission.

JSON to TypeScript

Instantly generate valid TypeScript interfaces from your JSON data.

Base64 Encoder

Easily encode and decode strings to and from Base64 format.