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📋 JSON Formatter & Validator

Paste your JSON below. We'll format it beautifully and catch any errors.

📚 How JSON Formatter Works

The JSON Formatter validates and formats JSON (JavaScript Object Notation) data to make it more readable. It checks syntax, detects errors, and organizes code with proper indentation.

🔍 What is JSON?

JSON is a lightweight data interchange format, easy for humans and machines to read. It's the de facto standard for web APIs, configuration files, and structured data storage.

🎯 When to Use

💡 Practical Examples

Example 1: Format minified JSON 
// Input (minified):
{"name":"John","age":30,"city":"NYC"}

// Output (formatted):
{
  "name": "John",
  "age": 30,
  "city": "NYC"
}
Example 2: Detect errors 
// ❌ Error: trailing comma
{
  "name": "John",
  "age": 30,
}

// Message: "Unexpected token } in JSON at position 30"

❓ Frequently Asked Questions

What's the difference between JSON and JavaScript Object?

JSON is a string in object format. Key differences:
• JSON requires double quotes on keys (JavaScript allows unquoted)
• JSON doesn't support functions or comments
• JSON is data-only, JavaScript objects can have methods

Does JSON Formatter store my data?

No! All processing happens in your browser (client-side). No data is sent to our servers. You can even use it offline.

How to fix "Unexpected token" in JSON?

Common errors:
• Trailing comma: {"a": 1,} ❌
• Single quotes: {'a': 1} ❌ (use double quotes)
• Unquoted keys: {a: 1} ❌ (use "a")
• Comments: JSON doesn't accept // or /* */

🔧 Technical Details

This tool uses native JavaScript JSON.parse() and JSON.stringify() for validation and formatting:

  1. Parsing: JSON.parse(input) validates syntax
  2. Formatting: JSON.stringify(parsed, null, spaces) applies indentation
  3. Minification: JSON.stringify(parsed) without spaces
💡 Pro Tip:

To validate JSON in your JavaScript code: 

try {
  const obj = JSON.parse(jsonString);
  console.log('✓ Valid JSON');
} catch (e) {
  console.error('✗ Invalid JSON:', e.message);
}