Format JSON Online - Best JSON Formatter

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data interchange format that's easy for humans to read and write, and easy for machines to parse and generate. It's based on a subset of the JavaScript Programming Language and is commonly used for transmitting data in web applications.

{
  "name": "John Doe",
  "age": 30,
  "city": "New York",
  "hobbies": ["reading", "swimming", "coding"],
  "address": {
    "street": "123 Main St",
    "zipCode": "10001"
  }
}

Why Format JSON?

Properly formatted JSON improves readability, makes debugging easier, and follows best practices for code maintainability. Our formatter helps you:

• Improve Readability: Consistent indentation and line breaks make JSON easier to read
• Debug Issues: Proper formatting helps identify syntax errors and structural problems
• Team Collaboration: Consistent formatting ensures all team members can easily understand the code
• Code Reviews: Well-formatted JSON makes code reviews more efficient and effective
• Documentation: Clean JSON is essential for API documentation and examples

JSON Best Practices

Follow these guidelines for clean, maintainable JSON:

• Use 2 or 4 spaces for indentation - Avoid tabs for consistency
• Always use double quotes - Single quotes are not valid in JSON
• No trailing commas - JSON doesn't allow commas after the last element
• Validate your JSON - Always check for syntax errors before using
• Use meaningful keys - Choose descriptive names for your properties
• Keep it simple - Avoid deeply nested structures when possible

Common JSON Errors

Here are the most frequent JSON formatting mistakes and how to fix them:

{
  "name": "John",
  "age": 30,  // ← This comma is invalid
}

{
  'name': 'John',  // ← Use double quotes
  "age": 30
}

{
  name: "John",  // ← Keys must be quoted
  "age": 30
}