Beautify minified JSON, validate syntax, compare two JSONs side-by-side, and minify for production. All processing happens in your browser—fast, private, and free.
Format, beautify, validate & minify JSON with syntax highlighting
Side-by-side diff with smart detection for objects and arrays
Repair trailing commas, missing quotes, and common errors
A powerful browser-based tool for formatting, validating, and transforming JSON data. Includes auto-fix, TypeScript generation, and advanced tools. All processing happens locally in your browser—your data never leaves your device.
The JSON Editor features a clean two-panel layout with a control bar for all operations. Input on the left, output on the right, controls at the top.
The left panel is where you enter your JSON data. You can paste JSON directly, type it manually, or load a sample to get started. The input supports any valid JSON including objects, arrays, and nested structures.
The right panel displays the processed result after you format, beautify, or minify your JSON. The output is read-only and includes options to copy to clipboard or download as a file.
The control bar provides quick access to all JSON operations. Configure indentation settings, format or minify your JSON, access the powerful Tools dropdown, and use utility functions like clear and sample loading.
Your JSON data never leaves your browser. Unlike many online tools that upload your data to remote servers, we process everything locally using JavaScript.
Detailed documentation for all available features. Click to expand each section.
Transform minified or messy JSON into clean, readable code with proper indentation. Formatting makes JSON easy to read, debug, and understand at a glance.
Adds consistent indentation and line breaks to make JSON human-readable. Choose from 2, 4, or 8 space indentation to match your project's style guidelines.
Proper indentation clearly shows the nesting level of objects and arrays. Each level is indented consistently, making parent-child relationships obvious.
Instantly check if your JSON is valid and get detailed error messages with line numbers when something is wrong. Catch syntax errors before they cause problems in your application.
When you click Format or Minify, the tool automatically validates your JSON. Invalid JSON displays a clear error message explaining what went wrong and where.
When JSON is invalid, the error message includes the position where parsing failed. This helps you quickly locate and fix the problem in your source data.
Detects common JSON mistakes: trailing commas, missing quotes around keys, single quotes instead of double quotes, unescaped special characters, and mismatched brackets.
Powered by the robust jsonrepair library, our tool can automatically fix a wide range of JSON errors. When invalid JSON is detected, the tool analyzes and repairs it with one click.
When your JSON has errors, the tool uses advanced parsing to automatically fix issues. Works with complex, nested JSON of any size. If repairs are possible, a 'Fix JSON' button appears with a summary of changes.
Converts single quotes to double quotes, adds missing quotes around keys, and properly escapes quotes within strings. Handles complex nested strings correctly.
Removes trailing commas, adds missing commas between elements, and fixes mismatched or missing brackets. Handles deeply nested structures.
Strips JavaScript-style comments (// line comments and /* block comments */) from the JSON. Handles comments anywhere in the structure.
Converts values from other languages: Python (True, False, None), JavaScript (undefined, NaN, Infinity), and unquoted strings to valid JSON equivalents.
Handles JSONP notation (callback wrapping), concatenated JSON objects, MongoDB-style data, and other special formats that contain valid JSON within.
Remove all unnecessary whitespace from your JSON to reduce file size. Minified JSON is ideal for production use, API payloads, and storage optimization.
Strips all spaces, tabs, and line breaks from your JSON while keeping it valid. The result is a single-line, compact representation perfect for transmission.
Minification typically reduces JSON file size by 10-30% depending on the original formatting. For large JSON files, this can significantly reduce bandwidth and storage costs.
Powerful transformation tools to manipulate your JSON structure. Sort keys, remove unwanted values, flatten nested structures, and more.
Recursively sorts all object keys in alphabetical order throughout the entire JSON structure. Makes JSON easier to compare and navigate, especially for configuration files.
Recursively removes all null values from objects and arrays. Helps clean up JSON data by eliminating empty or undefined fields.
Removes null values, empty strings (""), empty arrays ([]), and empty objects ({}) recursively. Provides thorough cleanup of sparse data.
Converts nested JSON structures into a flat object with dot-notation keys. Array indices are preserved as [0], [1], etc.
Converts a flat object with dot-notation keys back into a nested JSON structure. The reverse of the flatten operation.
Convert JSON to and from various encoded formats. Handle escaped strings, URL-encoded data, and Base64 encoding commonly encountered in web development.
Converts your JSON into an escaped string that can be safely embedded in code. Wraps the minified JSON in quotes with all internal quotes escaped.
Converts an escaped JSON string back into formatted JSON. Parses the outer string and then formats the inner JSON.
Decodes URL-encoded (percent-encoded) JSON strings. Handles %20, %22, %7B and other URL escape sequences.
Decodes Base64-encoded JSON strings. Commonly used for JWT payloads, API tokens, and encoded data transfer.
Generate code from your JSON data. Convert JSON structures into TypeScript interfaces and other code formats for use in your applications.
Automatically creates TypeScript interface definitions from your JSON structure. Infers types for all properties and handles nested objects and arrays.
Find specific data within large JSON structures and compare two JSON documents to identify differences. Essential tools for debugging and data analysis.
Search for keys or values within your JSON data. Results show the JSONPath to each match, making it easy to locate data in complex structures.
Side-by-side comparison of two JSON documents. Shows added, removed, and changed values with color-coded diff output. Perfect for tracking changes.
Easily copy your processed JSON to the clipboard or download it as a file. Multiple export options ensure you can use your JSON anywhere.
One-click copy of the entire output to your clipboard. The button shows confirmation when the copy is successful so you know it worked.
Downloads the output as a .json file with the name 'formatted.json'. The file is created locally in your browser - no server upload required.
Our JSON tools are designed for a wide range of use cases. Here are common scenarios where our formatter and validator can help.
Format API responses for debugging, validate request payloads before sending, and minify JSON for production deployments.
Quickly format JSON from logs, error messages, or console output to understand the data structure and identify issues.
Clean and format JSON data before importing into databases, converting to other formats, or using in applications.
Format JSON examples for documentation, tutorials, or learning materials. Clear formatting helps others understand the data structure.
Decode and analyze JWT tokens, Base64-encoded payloads, and URL-encoded data to understand authentication and authorization flows.
Compare JSON configurations, track changes between versions, and ensure consistent ordering for reliable diffs.
JSON has strict syntax rules that differ from JavaScript. Understanding these rules will help you avoid common errors.
{"name": "John"}{name: 'John'}All keys in JSON must be strings enclosed in double quotes. JavaScript allows unquoted keys, but JSON does not.
{"city": "New York"}{'city': 'New York'}JSON requires double quotes (") for all strings. Single quotes (') are not valid in JSON.
{"a": 1, "b": 2}{"a": 1, "b": 2,}Unlike JavaScript, JSON does not allow trailing commas after the last element in objects or arrays.
{"debug": true}{"debug": true} // enable debug modeJSON does not support comments of any kind. Remove all // and /* */ comments before parsing.
{"count": 42, "active": true, "data": null}{"count": undefined, "date": new Date()}JSON supports: strings, numbers, booleans, null, arrays, and objects. No undefined, functions, or JavaScript constructors.
Format and beautify JSON with customizable indentation.
Open EditorAutomatically repair invalid JSON errors with one click.
Fix JSONCompare two JSON files with semantic diff detection.
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