Formatting JSON online is quick and easy with the right tools:

Step-by-Step Process

1. Choose a formatter: Use JsonViewer.tools, JSON Editor Online, or similar
2. Input your JSON: Paste, upload file, or enter URL
3. Format automatically: Most tools format instantly
4. Copy formatted result: Use the formatted JSON in your project

Top Online JSON Formatters

JSON beautification transforms minified JSON into readable format with proper indentation and spacing:

What is JSON Beautification?

Beautification adds:

• Indentation: Proper spacing for nested objects
• Line breaks: Each key-value pair on separate lines
• Consistent spacing: Around colons and commas
• Readable structure: Clear hierarchy visualization

Before and After Example

{"name":"John","age":30,"city":"New York","hobbies":["reading","coding"]}

{
  "name": "John",
  "age": 30,
  "city": "New York",
  "hobbies": [
    "reading",
    "coding"
  ]
}

Beautification Methods

Fix JSON formatting errors using online tools that combine validation and formatting:

Common Formatting Errors

Error-Fixing Workflow

1. Identify errors: Use a validator to find issues
2. Use auto-repair: Many formatters fix common errors
3. Manual correction: Fix complex structural issues
4. Validate result: Ensure the JSON is valid
5. Format final output: Beautify for readability

Tools with Auto-Repair

• JSON Editor Online: Offers auto-repair suggestions
• JsonViewer.tools: Highlights and suggests fixes
• JSON Repair: Specialized tool for fixing broken JSON

JSON pretty print is the process of formatting JSON data to make it human-readable:

Pretty Print Features

• Indentation: Each nesting level is indented (usually 2 or 4 spaces)
• Line breaks: Each property on a separate line
• Consistent spacing: Proper spacing around operators
• Array formatting: Elements on separate lines for readability

Indentation Styles

{
  "user": {
    "name": "John",
    "details": {
      "age": 30,
      "city": "NYC"
    }
  }
}

{
    "user": {
        "name": "John",
        "details": {
            "age": 30,
            "city": "NYC"
        }
    }
}

{
	"user": {
		"name": "John",
		"details": {
			"age": 30,
			"city": "NYC"
		}
	}
}

When to Use Pretty Print

• Development: Making JSON readable during coding
• Debugging: Easier to spot issues in formatted JSON
• Documentation: Including readable JSON in docs
• Configuration files: Human-editable config files

Notepad++ can format JSON using plugins:

Installing JSON Viewer Plugin

1. Open Notepad++
2. Go to Plugins → Plugins Admin
3. Search for "JSON Viewer"
4. Install and restart Notepad++

Formatting JSON

1. Open your JSON file in Notepad++
2. Select all JSON content (Ctrl+A)
3. Go to Plugins → JSON Viewer → Format JSON
4. Your JSON will be beautifully formatted

JSON Viewer Features

• Format JSON: Pretty print with indentation
• Compress JSON: Minify to single line
• Tree View: Hierarchical view in side panel
• Validation: Syntax error highlighting

Alternative: XML Tools Plugin

For basic formatting without JSON-specific features:

1. Install XML Tools plugin
2. Use Plugins → XML Tools → Pretty Print
3. Works for JSON with some limitations

VS Code has excellent built-in JSON formatting capabilities:

Built-in Formatting

Formatting Settings

Customize JSON formatting in settings.json:

{
  "[json]": {
    "editor.defaultFormatter": "vscode.json-language-features",
    "editor.tabSize": 2,
    "editor.insertSpaces": true,
    "editor.formatOnSave": true
  }
}

Useful Extensions

• Prettier: Advanced formatting with more options
• JSON Tools: Additional JSON utilities
• Auto Rename Tag: Helps with JSON editing

Command line JSON formatting is perfect for automation and batch processing:

Using jq (Recommended)

# Format JSON file
jq . input.json > formatted.json

# Format from stdin
echo '{"name":"John","age":30}' | jq .

# Pretty print with custom indentation
jq --indent 4 . input.json

# Sort keys alphabetically
jq -S . input.json

# Compact output (minify)
jq -c . input.json

# Format multiple files
for file in *.json; do jq . "$file" > "formatted_$file"; done

Using Python

# Format JSON file
python -m json.tool input.json > formatted.json

# Format with custom indentation
python -c "
import json
with open('input.json') as f:
    data = json.load(f)
with open('formatted.json', 'w') as f:
    json.dump(data, f, indent=4, sort_keys=True)
"

Using Node.js

# One-liner formatting
node -e "console.log(JSON.stringify(JSON.parse(require('fs').readFileSync('input.json')), null, 2))"

# With file output
node -e "
const fs = require('fs');
const data = JSON.parse(fs.readFileSync('input.json'));
fs.writeFileSync('formatted.json', JSON.stringify(data, null, 2));
"

The best JSON formatter depends on your specific needs and workflow:

For Quick Online Formatting

For Development Workflow

• VS Code: Best for integrated development
• Notepad++: Good for Windows users
• Sublime Text: Fast and customizable
• Command line (jq): Perfect for automation

Selection Criteria

Custom indentation allows you to control the spacing and appearance of formatted JSON:

Programming Language Examples

JavaScript

// 2-space indentation
JSON.stringify(data, null, 2)

// 4-space indentation  
JSON.stringify(data, null, 4)

// Tab indentation
JSON.stringify(data, null, '\t')

// Custom string indentation
JSON.stringify(data, null, '---')

Python

# 2-space indentation
json.dumps(data, indent=2)

# 4-space indentation
json.dumps(data, indent=4)

# Tab indentation
json.dumps(data, indent='\t')

Command Line (jq)

# Custom indentation (2-8 spaces)
jq --indent 2 . input.json
jq --indent 4 . input.json
jq --indent 8 . input.json

# Tab indentation
jq --tab . input.json

Online Tools with Custom Indentation

• JSON Editor Online: Configurable spacing in settings
• JsonViewer.tools: Standard 2-space indentation
• Code Beautify: Options for different indent sizes

Best Practices

• 2 spaces: Most common, good for web development
• 4 spaces: Better readability for complex structures
• Tabs: Personal preference, configurable in editors
• Consistency: Use the same indentation across your project

JSON minification removes all unnecessary whitespace to reduce file size:

Why Minify JSON?

• Reduced file size: Faster network transfers
• Storage efficiency: Less disk space usage
• API responses: Faster loading times
• Production deployment: Optimized for performance

Minification Methods

Online Tools

• JsonViewer.tools: Toggle between formatted and minified
• JSON Minifier: Dedicated minification tools
• Code Beautify: Minify option available

Programming Languages

// JavaScript
JSON.stringify(data) // No spacing parameter = minified

// Python  
json.dumps(data, separators=(',', ':')) // Compact separators

// Command line (jq)
jq -c . input.json // Compact output

Before and After Example

{
  "name": "John Doe",
  "age": 30,
  "city": "New York",
  "hobbies": [
    "reading",
    "coding",
    "traveling"
  ]
}

{"name":"John Doe","age":30,"city":"New York","hobbies":["reading","coding","traveling"]}