JSON Formatter & Validator

Format, validate, and analyze JSON data with indentation and structure info.

Status

Valid JSON

Keys

3

Formatted

{
  "name": "John",
  "age": 30,
  "skills": [
    "JS",
    "React"
  ]
}

JSON Stats

ValidYes
Total Keys3
Max Depth2
Size48 bytes

Use the JSON Formatter & Validator above to calculate your results. Enter your values and see instant results — all calculations run in your browser.

Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.

How It Works

A JSON Formatter & Validator ensures your JSON data is correctly structured and easily readable. It's crucial for developers and data analysts to prevent parsing errors and maintain data integrity, especially in APIs and configuration files.

This tool utilizes a parser to traverse the JSON structure, checking for syntax errors like missing commas, incorrect brackets, or invalid data types. It then indents and formats the output based on a predefined style guide (e.g., 2-space or 4-space indentation) for improved readability.

Always validate your JSON before using it in production environments to catch subtle syntax errors. Be aware that even a single misplaced comma or bracket can render an entire JSON payload invalid, leading to application failures.

Example: Validating and Formatting an API Response$

  1. 1 Input the following unformatted and potentially invalid JSON string: {"user":"Jane Doe", "age":30, "email":"[email protected]" "city":"New York"}
  2. 2 The formatter identifies the missing comma between the 'email' and 'city' fields, then applies standard indentation. It also flags the missing comma as a validation error.
  3. 3 The validated and formatted output would be: { "user": "Jane Doe", "age": 30, "email": "[email protected]", "city": "New York" }
  4. 4 This example shows how the tool not only makes the JSON readable but also pinpoints critical syntax errors that would break data processing in an application.

Source: IETF · Last updated: April 2026

Frequently Asked Questions

How do you format JSON for readability?
Use indentation (2 or 4 spaces) for nested objects and arrays. Paste your JSON into this formatter to auto-indent, validate syntax, and highlight errors. Most code editors also have built-in JSON formatting.
What are common JSON syntax errors?
The most common errors are trailing commas after the last item, single quotes instead of double quotes, unquoted keys, and missing commas between items. JSON requires double quotes for all strings and keys.
What is the difference between JSON and a JavaScript object?
JSON requires double-quoted keys and string values, does not allow trailing commas, and cannot contain functions or undefined. JavaScript objects are more flexible. JSON is a strict subset of JavaScript object notation.

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