JSON Formatter & Beautifier
Format and beautify your JSON data with customizable indentation. Pretty print JSON online with 2, 4, 6, or 8 space indentation. Free and secure.
Why Use a JSON Formatter & Validator?
APIs and databases generally transmit data in a compressed, single-line format to save bandwidth. Our JSON beautifier online reverses this process, allowing developers to debug complex nested arrays effortlessly.
| Core Feature | How it Works | Developer Benefit |
|---|---|---|
| Pretty Print JSON | Injects proper line breaks between every key-value pair and array item. | Makes raw payload data instantly readable for humans. |
| Smart Indentation | Aligns nested objects using 2, 4, or 8 spaces based on your preference. | Clarifies the hierarchy and depth of complex JSON trees. |
| Strict Validation | Parses the text against standard ECMA-404 JSON syntax rules. | Locates missing commas, trailing quotes, or unexpected tokens instantly. |
| Secure Local Execution | Processes the JSON.stringify() logic entirely in your DOM. | Guarantees 100% privacy; no sensitive payload is sent over the network. |
Live Examples: Format JSON String Online
Watch how our tool transforms unreadable data blocks into perfectly structured code.
Example 1: Pretty Print Minified JSON
When you fetch data from a REST API, it often arrives as a dense block. Click to format it:
{"company":"JSONEscape","established":2026,"services":["escape","minify","format"],"active":true}{
"company": "JSONEscape",
"established": 2026,
"services": [
"escape",
"minify",
"format"
],
"active": true
}Example 2: Validate & Fix Errors
Notice the missing comma after "superuser"? Our JSON validator will catch it immediately, highlight the line, and prevent you from pushing bad code.
{
"user": "admin",
"role": "superuser"
"token": "expired"
}Invalid JSON: Expected ',' or '}' after property value in JSON at position 40Frequently Asked Questions
How do I format JSON online?
Paste your minified or unformatted JSON into the input editor and it will be automatically formatted with proper indentation. You can choose between 2, 4, 6, or 8 space indentation using the indent selector in the toolbar. The formatted output appears instantly in the output panel.
What is the best indentation size for JSON?
The most common indentation sizes are 2 spaces (standard for most projects and the npm ecosystem) and 4 spaces (more readable for complex, deeply nested structures). Choose the indentation that best fits your project style guide or personal preference.
Can I download the formatted JSON?
Yes, click the Download button in the output toolbar to save the formatted JSON as a .json file. The file will be saved with proper formatting and UTF-8 encoding, ready to use in your projects.
Why does my JSON fail to format?
JSON formatting will fail if the input contains syntax errors such as missing commas, unmatched brackets, trailing commas, or single quotes instead of double quotes. The tool will highlight the error line and display the error message. Fix these errors and try formatting again.
How to create a JSON file?
Learning how to create a JSON file is incredibly simple and requires no special software. You can use any standard plain text editor built into your operating system, such as Notepad (for Windows) or TextEdit (for Mac). Open your text editor (do not use rich-text processors like MS Word), type or paste your structured JSON data into the blank document, go to File > Save As, change the file extension from .txt to .json (for example: data.json) and click save. Pro Tip: A single missing comma or bracket can break your file. Before saving, always paste your raw text into our free online JSON formatter and validator above to instantly check for syntax errors and pretty-print your code.
How to open .json files?
Since a .json file is essentially a plain text document, you do not need any specialized software. On Windows, right-click the file, select "Open with," and choose Notepad. On Mac, right-click and choose TextEdit. You can also drag and drop the file directly into Chrome, Edge, or Firefox. However, the data is often compressed into a single, messy line. For the best experience, copy all the text and paste it into our free JSON Formatter above to instantly beautify it with color-coding and proper indentation.