JSON整形・比較
The JSON Formatter & Diff tool beautifies compressed JSON data and visually compares differences between two JSON files. Features include indent customization and validation. All processing happens in your browser, ensuring safe handling of JSON with sensitive information.
Free JSON formatter and comparison tool. Format API responses and JSON files for better readability, and compare two JSONs for differences. Browser-based processing ensures secure handling of sensitive data.
What You Can Do
The JSON Formatter Tool is a browser-based tool for formatting compressed JSON data and comparing differences between two JSON files. Perfect for debugging API responses, checking configuration file changes, and securely processing JSON with sensitive information. All processing is done in your browser, and data is never sent to servers.
- ✅ Format: Beautify compressed JSON or minify formatted JSON
- ✅ Compare (Diff): Visually display differences between two JSONs
- ✅ Security: Browser-based processing ensures data safety
📝 JSON Input
📄 Formatted Result
🔒 All processing is done in your browser. Data is never sent to servers.
💡 Use Cases
- Format API response JSON for better readability
- Debug compressed JSON easily
- Check differences between two JSON files
- Verify changes in configuration files
- Securely process JSON with sensitive information (browser-based)
❓ FAQ
No, all processing is done in your browser. You can safely use this tool even with JSON containing sensitive information.
JSON files up to a few MB can be processed without issues. However, very large files may slow down your browser.
This tool is designed specifically for JSON. Invalid JSON will trigger error messages.
Currently, comparison results are displayed on-screen only. You can take a screenshot or manually copy the results if needed.
📚 JSON Basics
🔍 Common JSON Parsing Errors
When JSON fails to parse, it's usually due to these syntax errors:
- Trailing Comma:
{"name": "John", "age": 30,}- comma after the last element - Single Quotes: JSON only accepts double quotes (
").{'name': 'John'}is invalid - Unquoted Keys:
{name: "John"}- key names must be quoted - Invalid Line Breaks: Line breaks (
\n) in strings must be escaped - Comments: JSON does not officially support comments (
//,/* */) except in JSONC format
💡 This tool displays error positions and messages when your JSON contains syntax errors.
🔒 Security Benefits of Browser-Based Processing
This tool performs all processing in your browser (JavaScript). This provides important security benefits:
- Zero Data Leak Risk: Input JSON is never sent to servers. You can safely process JSON containing API keys, passwords, or other sensitive information.
- No Network Interception: Since no network communication occurs, there's no risk of MITM attacks or packet sniffing.
- No Server Logs: Your JSON data won't be recorded in access logs or error logs on servers.
⚠️ When using online JSON formatting tools, always verify they are "browser-based." Server-side tools may leak sensitive information to third parties.
⚖️ JSON vs XML: Format Comparison
Here are the key differences between JSON (JavaScript Object Notation) and XML (eXtensible Markup Language), commonly used for web APIs and data exchange:
| Aspect | JSON | XML |
|---|---|---|
| Readability | Simple and easy to read | Verbose tags reduce readability |
| Data Size | Lightweight (30-40% smaller on average) | Larger due to tags |
| Parse Speed | Fast (native JavaScript) | Slower (requires DOM parser) |
| Data Types | Numbers, strings, booleans, null, arrays, objects | All strings (type info in attributes) |
| Metadata | None | Can describe metadata with attributes |
| Primary Use | REST APIs, Web APIs, config files | SOAP, RSS, complex document structures |
📌 In modern web development, JSON is the standard for REST APIs and configuration files. XML is used for legacy SOAP APIs and specific industry standards (banking, healthcare, etc.).
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