JSON FORMATTER
Format, validate & transform JSON instantly
Everything runs locally in your browser. Your data never leaves your device - no uploads, no servers, no data transmission.
All processing happens directly on your machine using JavaScript. Close the tab and all JSON data is gone.
Operation mode
JSON Quick reference
Data types
{
"string": "text",
"number": 42,
"boolean": true,
"null": null,
"array": [1, 2, 3],
"object": {"key": "value"}
}
JSONPath examples
$- Root object$.key- Direct child$..key- Recursive descent$[*]- All array items$[0]- First item$[-1]- Last item$[0:2]- Range$[?(@.price < 10)]- Filter
Common patterns
{"status": 200, "data": {...}}
{"version": "1.0", "settings": {...}}
{"items": [...], "total": 10}
Formatting analytics
How to use JSON Formatter & Validator
Format, validate, and transform JSON data in seconds
Full Documentation DocsChoose mode
Select your operation mode
Input JSON
Paste data or upload files
Get results
Copy or download formatted JSON
Why choose this JSON formatter?
8 modes, tree view, diff, CSV export
Safe JSON Parsing
Uses native JSON.parse() with error handling to safely process your data without breaking anything.
Maximum compression
Reduce file sizes by removing whitespace and unnecessary characters while preserving data integrity.
Side-by-side diff
Compare two JSON files instantly with syntax highlighting and visual difference indicators.
Syntax validation
Detect errors with detailed validation messages showing exactly what's wrong and where.
Customizable options
Fine-tune formatting with indentation settings, sorting options, and custom configurations.
8 operation modes
Format, Minify, Tree View, Diff, JSONPath queries, JSON-to-CSV conversion, Transform, and Validate - all in one tool.
Frequently Asked Questions
Everything you need to know about JSON formatting
What is JSON formatting?
JSON formatting (beautification) converts compact JSON into readable format with proper indentation, line breaks, and consistent formatting to make it easier to read and edit.
Is JSON validation safe?
Yes. This tool uses native JSON.parse() with try-catch error handling to safely validate JSON without executing any code or compromising security.
How much can I reduce JSON file size?
Typically 10-30% reduction, depending on formatting. Well-formatted JSON with lots of whitespace can be reduced even more through minification.
What is JSON minification?
JSON minification removes all unnecessary whitespace, line breaks, and indentation to create the smallest possible file size while maintaining valid JSON structure.
Will minification break my JSON?
No. Minification only removes whitespace and formatting. It doesn't change the data structure or values. Always test in your environment though.
Can I customize formatting settings?
Yes. Choose indentation size (2 or 4 spaces), enable key sorting, or use custom configurations for specific formatting needs.
Is my JSON data safe with this tool?
Yes. Everything runs locally in your browser. Your JSON data never leaves your device - nothing is uploaded or stored anywhere.
Technical Details
Under the hood of this JSON formatter online tool
JSON Parsing Engine
This JSON formatter uses the native JSON.parse() and JSON.stringify() APIs with configurable indentation (2 or 4 spaces, tabs, or compact). The parser validates input against the ECMA-404 JSON standard, detecting syntax errors with precise line and column numbers. Key sorting and null removal options are available for all output modes.
Tree View & Navigation
The JSON validator builds an interactive tree visualization from parsed data, supporting expand/collapse at any nesting level. JSONPath query support enables targeted extraction of nested values using dot notation, bracket notation, wildcards, recursive descent, and array slicing syntax.
Minification & Transform
The JSON beautifier minifies output by stripping all whitespace for significant file size reduction. Sort keys alphabetically for consistent output and easier diff comparison. Key transformation supports camelCase, snake_case, kebab-case, and UPPER_CASE conventions. Processing capacity depends on available browser memory.
Format Conversion
Convert JSON to CSV with structure-aware mapping. The JSON to CSV converter flattens nested objects into tabular columns with dot-notation headers. Diff mode compares two JSON documents side by side with text-based comparison, highlighting added, removed, and changed lines between the original and modified versions.