📋 JSONFormatter

中文
Formatted result will appear here...
🎨

Syntax Highlighting

Automatically colorizes keys, strings, numbers, and booleans for easy reading.

✅

Instant Validation

Real-time JSON syntax error detection with detailed error messages and positions.

🌳

Tree View

Expandable/collapsible tree structure for browsing complex JSON data easily.

🔄

Beautify/Minify

Toggle between beautified and minified formats with customizable indentation.

🔒

100% Private

All processing happens locally in your browser. No data is ever uploaded to any server.

💯

Completely Free

No registration, no limits. Free to use forever.

Related Articles

What is JSON? A Complete Beginner's Guide to Data Interchange

Learn JSON from scratch — understand its syntax rules, data types, and why it became the go-to data interchange format for modern web development.

Beginner Guide

JSON Development Best Practices: Building Quality API Data Structures

Master JSON naming conventions, structure design, error handling, and more to make your APIs more professional and maintainable.

Best Practices

JSON vs XML: The Modern Data Format Showdown

An in-depth comparison of JSON and XML across syntax, performance, readability, and more — helping you make the right format choice for your project.

Comparison

JSON Schema Validation: A Complete Tutorial

Learn how to use JSON Schema to define data structures and validate API inputs/outputs — from basic syntax to advanced applications.

Advanced

Frequently Asked Questions

What is JSON?
JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy for humans to read and write, and easy for machines to parse and generate. It is widely used for API data transmission.
Is my JSON data uploaded anywhere?
No. All formatting and validation happens entirely in your browser. Your data never leaves your device, ensuring complete privacy.
How large a JSON file can I process?
It depends on your browser's memory. Generally, JSON files up to several MB can be processed smoothly. Very large files may be slower.
What indentation formats are supported?
We support 2 spaces, 4 spaces, and Tab indentation. You can switch between them using the dropdown in the toolbar.
What does the JSON validator check?
The validator checks JSON syntax correctness, including bracket matching, comma placement, string quotes, and more. Errors are displayed with specific positions and messages.