Online JSON Formatter & Beautifier

Online JSON Format & Beautifier, clean, restructure, and flatten your JSON data instantly using this online JSON formatter. This tool helps developers improve readability, enforce consistent key formatting, apply dot notation flattening for nested objects, and prepare structured JSON for APIs, databases, or debugging.

All processing runs directly in your browser no data is uploaded to any server.

This tool automatically:

  • Groups arrays into blocks of 10 items per line
  • Prevents extremely long horizontal lines
  • Keeps nested array structure intact

Example

Input Minified JSON:

JSON
{"user":{"profile":{"name":"Alice","age":"28"},"active":true,"skills": ["js","php","css","html","node","mysql","git","api","docker","linux","aws","nginx"]}}

Formatted JSON:

JSON
{
	"user" : {
		"profile" : {
			"name" : "Alice",
			"age" : "28"
		},
		"active" : true,
		"skills" : [
			"js", "php", "css",
			"html", "node", "mysql",
			"git", "api", "docker",
			"linux", "aws", "nginx"
		]
	}
}

⚙️ Online JSON Formatter

Format, beautify, validate, and transform your JSON data instantly with this powerful online JSON formatter. Improve readability by organizing large arrays, sorting object keys, converting key case formats (camelCase, snake_case, PascalCase, kebab-case), handling number types, and even flattening nested JSON using dot notation.

This tool supports both valid JSON and JavaScript object-style code. You can paste standard JSON with quoted keys, or JavaScript-style objects where keys are not wrapped in quotes.

Note: If you paste JavaScript object style code, the editor may show JSON syntax warnings because unquoted keys are not valid JSON. You can safely ignore these warnings and click "Format JSON". The tool will automatically normalize the input, convert it into proper JSON format, and generate the correctly formatted output.

Example code:
Sample JSON
JSON Input
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Splitoptions

Options

?Choose how JSON output is indented - 2 spaces, 4 spaces, or tabs for easier readability and consistent formatting.
?Convert all object keys to a consistent format
?Control how numeric values are formatted.
Keep as numbers: {"age" :> 25}
Convert to strings: {"age" : "25"}
Detect numeric strings: {"age" : 25}
?Organize JSON object properties alphabetically, especially for large JSON objects.
?Convert deeply nested JSON objects into a single-level structure using dot notation. Example:
{ "user": { "name": "John" } }
becomes { "user.name": "John" }.
?Improve readability by grouping large arrays into smaller blocks (e.g., 10 items per line). Prevents extremely long single-line arrays and makes large JSON datasets easier to read, review, and compare.
?Apply chunk formatting only if array length is greater than this value.
?Number of array items to display per line in the output.
Formatted JSON Output
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✨JSON Formatting Features

Everything you need to clean, transform, and structure JSON efficiently.

🔤 Key Case Conversion

Convert object keys between camelCase, snake_case, PascalCase, and kebab-case instantly.

🔢 Number Handling

Convert numeric strings to numbers, numbers to strings, and preserve decimal precision.

🔠 Sort Object Keys

Alphabetically sort keys (A–Z or Z–A) with optional deep sorting for nested objects.

🔗 Flatten Nested JSON

Transform deeply nested objects into dot notation for easier data handling and debugging.

📦 Chunk Large Arrays

Improve readability by grouping large arrays into structured blocks.

📏 Custom Indentation

Choose 2 spaces, 4 spaces, tabs, or custom indentation to match your coding standards.

🔒 100% Client-Side & Secure

All formatting and transformations happen directly in your browser. Your JSON data is never uploaded, stored, or processed on any server ensuring complete privacy and security.

❓ Frequently Asked Questions (FAQ)

What is a JSON formatter?

A JSON formatter is a tool that beautifies and structures raw JSON data by adding proper indentation, spacing, and organization to improve readability and debugging.

Is this JSON formatter free to use?

Yes. The tool is completely free and works directly in your browser without requiring registration.

Is my JSON data secure?

Yes. All processing happens 100% client-side in your browser. Your JSON data is never uploaded, stored, or shared.

Can this tool handle large JSON files?

Yes. It supports large arrays and nested objects. You can also enable array chunking to improve readability for very large datasets.

What is 'Flatten Nested JSON (Dot Notation)'?

This option converts deeply nested JSON objects into a single-level structure using dot notation. It is useful for form data processing, query parameters, CSV export, and database operations.

Does sorting object keys change my data?

No. Sorting only changes the order of object keys for better consistency and comparison. The actual values remain unchanged.

What does number handling do?

Number handling allows you to convert numeric strings into actual numbers or convert numbers into strings, depending on your formatting needs.

Can I convert key naming styles?

Yes. You can transform object keys into camelCase, snake_case, PascalCase, or kebab-case to match your coding standards or API requirements.

Can I customize indentation?

Yes. You can choose between 2 spaces, 4 spaces, tabs, or custom indentation sizes.

Does this tool validate JSON?

Yes. The formatter detects invalid JSON syntax and helps you identify formatting issues before generating output.

Does this tool support JavaScript object-style code?

Yes. In addition to standard JSON, the tool accepts JavaScript object-style code with unquoted keys. Even if the editor shows JSON warnings, you can format the input and the tool will automatically normalize it into valid JSON.

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