JSON validator & beautifier

Validate JSON content and make it looks good.

Tool: JSON Validator
Type: Data Formatting

JSON validator & beautifier

Validate & Format JSON
Paste minified or poorly formatted JSON
Key Features
  • Validate JSON syntax
  • Auto-beautify formatting
  • Detect syntax errors
  • One-click copy
  • No registration required

How to Use

1
Paste JSON

Enter your JSON code

2
Validate

Check for syntax

3
Beautify

Format nicely

4
Copy Result

One-click copy

Before & After Examples

❌ Minified JSON:
{"name":"John","age":30,"city":"New York"}
✅ Beautified JSON:
{
  "name": "John",
  "age": 30,
  "city": "New York"
}
❌ Minified JSON:
{"users":[{"id":1,"name":"Alice"},{"id":2,"name":"Bob"}],"count":2}
✅ Beautified JSON:
{
  "users": [
    {
      "id": 1,
      "name": "Alice"
    },
    {
      "id": 2,
      "name": "Bob"
    }
  ],
  "count": 2
}
❌ Invalid JSON (Will show error):
{"name": "John", "age": 30,}

Error: Trailing comma after last property

Common JSON Errors

Trailing Comma

Wrong: {"name": "John",}
Right: {"name": "John"}
Don't add comma after last element.

Unquoted Keys

Wrong: {name: "John"}
Right: {"name": "John"}
Keys must be quoted strings.

Single Quotes

Wrong: {'name': 'John'}
Right: {"name": "John"}
Only double quotes allowed.

Missing Braces

Wrong: "name": "John", "age": 30
Right: {"name": "John", "age": 30}
Root must be object or array.

Perfect For

Web Development

Debug API responses, validate config files, and check JSON data structures.

Debugging

Find syntax errors in minified JSON and quickly identify issues.

Data Analysis

Format JSON data for better readability and understanding structure.

API Integration

Validate API responses and ensure data integrity before processing.

Why Choose Our Tool?

⚡
Instant Validation

Real-time checking

✨
Auto-Beautify

Perfect formatting

🎯
Error Detection

Clear messages

📋
Easy Copy

One-click copying

📱
Mobile Friendly

Works everywhere

🆓
100% Free

No registration

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JSON Validation & Beautification Guide

Understanding JSON Validation and Beautification

JSON (JavaScript Object Notation) is a universal data format used for APIs, configuration files, and data interchange. While JSON is human-readable by design, minified JSON (used for transmission efficiency) becomes difficult to read and debug. JSON validators check syntax correctness, while beautifiers format JSON for readability. This tool combines both functions to help developers quickly identify and fix JSON errors.

Why JSON Validation Matters

  • Error Detection: Find syntax errors immediately
  • Debugging: Identify missing quotes, commas, or braces
  • API Testing: Validate responses before integration
  • Data Quality: Ensure data integrity and correctness
  • Development Speed: Fix issues before deployment

JSON Formatting Best Practices

Well-formatted JSON uses consistent indentation (2-4 spaces), puts opening braces on the same line, and uses proper spacing around colons and commas. This makes JSON easier to read, debug, and understand. Beautified JSON is essential for development but can be minified for production to reduce file sizes.

Common JSON Mistakes

  • Trailing Commas: `{"key": "value",}` is invalid
  • Unquoted Keys: Keys must be quoted strings
  • Single Quotes: JSON requires double quotes, not single
  • Missing Braces: Root element must be object or array
  • Invalid Escapes: Newlines must be escaped as \n

When to Use Minified vs Beautified JSON

Use Minified JSON: For production APIs, network transmission, and storage efficiency. Use Beautified JSON: For development, debugging, documentation, and readability. Most tools automatically minify JSON before transmission and beautify it for debugging, making validation crucial for development workflows.

Pro Tip: Always validate JSON from external sources (APIs, user input) before using it in your application. Invalid JSON can break your code.

Frequently Asked Questions

Validation checks JSON syntax for errors. Beautification formats JSON for readability. This tool does both: validates the syntax and formats it nicely.
Yes! Paste minified JSON (all on one line) and it will be automatically beautified with proper indentation and formatting.
The tool will show you a clear error message indicating what's wrong and where the error is located in your JSON.
No! Beautification only changes formatting (spacing, indentation). The actual data remains completely unchanged.
Yes! Use the copy button to easily copy the beautified JSON to your clipboard with one click.
This tool supports standard JSON (RFC 7158). No extensions like comments or trailing commas are allowed.
The tool handles reasonably large JSON documents. For extremely large files, consider using server-side validation.
Yes! Our JSON Validator & Beautifier is completely free with no hidden fees, premium features, or registration requirements.

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