A lightweight Chrome extension for formatting and viewing JSON data
Features • Installation • Usage • Development
- 🚀 Auto Detection - Automatically formats JSON when visiting API endpoints
- 🌳 Tree View - Collapsible tree structure with line numbers
- 🎨 Syntax Highlighting - Color-coded JSON keys, values, and types
- 🌙 Dark Mode - Toggle between light and dark themes
- 📋 Copy & Edit - One-click copy, built-in JSON editor
- 🔧 Format Tools - Format, compress, escape, and unescape JSON
- 🐍 Python Dict Support - Parse Python dict format (single quotes, True/False/None)
- ➕ Trailing Comma - Tolerant parsing of trailing commas
| Viewer | Editor | Dark Mode |
|---|---|---|
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👉 Install from Chrome Web Store
- Download or clone this repository
- Run
npm install && npm run build - Open
chrome://extensions/in Chrome - Enable "Developer mode"
- Click "Load unpacked" and select the
distfolder
Simply visit any URL that returns JSON data - the extension will automatically detect and format it.
- Click the extension icon in toolbar
- Paste your JSON in the left panel
- View formatted result in the right panel
| Button | Action |
|---|---|
| ↑/↓ | Collapse/Expand one level |
| ⇈/⇊ | Collapse/Expand all |
| 📋 | Copy to clipboard |
| 🌙/☀️ | Toggle theme |
⌘/Ctrl + F- Format JSON
- Node.js 16+
- npm or yarn
# Install dependencies
npm install
# Development build with watch
npm run dev
# Production build
npm run buildujson/
├── manifest.json # Extension manifest
├── package.json # Dependencies
├── vite.config.js # Build config
├── viewer.html # Auto-format page
├── editor.html # Editor page
├── icons/ # Extension icons
├── src/
│ ├── background.js # Service worker
│ ├── content.js # Content script
│ ├── ViewerApp.vue # Viewer component
│ ├── EditorApp.vue # Editor component
│ ├── components/ # Vue components
│ │ ├── JsonViewer.vue
│ │ ├── JsonNode.vue
│ │ └── JsonValue.vue
│ ├── utils/
│ │ └── jsonFormat.js # JSON utilities
│ └── styles/
│ └── theme.css # Theme variables
└── dist/ # Build output
- Framework: Vue 3 + Composition API
- Build Tool: Vite
- Extension: Chrome Manifest V3
MIT License - see LICENSE for details.
This extension does not collect any user data. See Privacy Policy for details.
Contributions are welcome! Please feel free to submit a Pull Request.
- Fork the repository
- Create your feature branch (
git checkout -b feature/amazing) - Commit your changes (
git commit -m 'Add amazing feature') - Push to the branch (
git push origin feature/amazing) - Open a Pull Request
If you have any questions or suggestions, please open an issue.
Made with ❤️ by uuhc


