JSON Formatter & Validator
Format, validate, and beautify your JSON data instantly. Free online tool with real-time validation, tree view, and minification.
Input
0 charactersOutput
Formatted output will appear here...Features
JSON Formatting
Pretty-print your JSON with customizable indentation. Choose between 2 spaces, 4 spaces, or tabs.
Real-time Validation
Instantly validate your JSON as you type. Get clear error messages with line and column numbers.
Tree View
Visualize your JSON structure with an interactive tree view. Expand and collapse nodes easily.
JSON Minifier
Compress your JSON by removing all whitespace. Perfect for reducing file size and API payloads.
Copy & Download
Copy formatted JSON to clipboard or download as a .json file with one click.
100% Client-Side
Your data never leaves your browser. All processing happens locally for maximum privacy and security.
How to Use
Paste Your JSON
Copy and paste your JSON data into the input panel on the left, or click "Load Sample" to try with example data.
Format or Validate
Click "Format" to beautify your JSON, or watch real-time validation as you type. Errors are highlighted with line numbers.
Copy or Download
Copy the formatted output to your clipboard or download it as a .json file. Switch to Tree View to explore the structure visually.
Frequently Asked Questions
What is JSON and why do I need a formatter?
JSON (JavaScript Object Notation) is a lightweight data format used for data exchange between servers and web applications. A JSON formatter helps you read and debug JSON by adding proper indentation and line breaks, making the structure clearer and easier to understand.
Is my data secure when using this JSON formatter?
Yes, absolutely. This JSON formatter runs entirely in your browser. Your data is never sent to any server. All processing happens locally on your device, ensuring complete privacy and security of your data.
What's the difference between formatting and minifying JSON?
Formatting (or beautifying) adds whitespace, indentation, and line breaks to make JSON human-readable. Minifying does the opposite - it removes all unnecessary whitespace to reduce file size, which is useful for production deployments and API responses.
How does the JSON validator detect errors?
Our JSON validator uses the browser's native JSON parser to check your data against the JSON specification. When an error is found, it shows you the exact error message along with the line and column number where the problem occurs, helping you quickly locate and fix issues.
Can I use this tool for large JSON files?
Yes, this tool can handle reasonably large JSON files since all processing happens in your browser. However, very large files (several megabytes) may cause performance slowdowns depending on your device's capabilities. For extremely large files, consider using command-line tools.
What common JSON errors does this validator catch?
The validator catches all JSON syntax errors including: missing or extra commas, unquoted keys or strings, single quotes instead of double quotes, trailing commas, unclosed brackets or braces, invalid escape sequences, and malformed numbers.