A lightweight Chrome extension for formatting, validating, and exploring JSON data with an interactive tree view.
- ✅ Validate JSON with detailed error messages including line and column numbers
- 🎨 Pretty-print with configurable indent (2 spaces, 4 spaces, or tabs)
- 📦 Minify JSON to remove all whitespace
- 🔍 Interactive tree view with collapsible nodes and type indicators
- 🔤 Sort object keys alphabetically
- 📊 Export to CSV for flat arrays of objects
- 📋 Copy to clipboard with one click
- 💾 Download as
.jsonor.csvfile - 🌓 Dark/light mode with automatic OS theme detection
- ⌨️ Keyboard shortcuts (Escape to clear, Ctrl/Cmd+Enter to format)
- 🔒 100% offline — no data ever leaves your browser
- Download or clone this repository
- Open Chrome and navigate to
chrome://extensions/ - Enable "Developer mode" (toggle in top-right corner)
- Click "Load unpacked"
- Select the extension directory
- Paste or type JSON into the input area
- Click Format to pretty-print with the selected indent style
- Click Minify to compress JSON to a single line
- Click Validate to check if JSON is valid without formatting
- After formatting or minifying, switch to the Tree View tab
- Click the ▼ icon next to objects or arrays to expand/collapse
- Values are color-coded by type:
- Green — strings
- Red — numbers
- Purple — booleans
- Gray — null
- Blue — object keys
If your JSON is an array of objects with consistent keys (like a table), the ↓ .csv button will appear after formatting. Click it to download a CSV file.
Example:
[
{ "name": "Alice", "age": 30, "city": "NYC" },
{ "name": "Bob", "age": 25, "city": "LA" }
]Exports to:
name,age,city
Alice,30,NYC
Bob,25,LA- Indent: Choose between 2 spaces, 4 spaces, or tabs
- Sort keys: Check this to alphabetically sort all object keys
Escape— Clear all input and outputCtrl/Cmd + Enter— Format JSON
When JSON is invalid, you'll see detailed error messages like:
Invalid JSON: Unexpected token } in JSON (line 5, column 12)
This tells you exactly where the syntax error occurred so you can fix it quickly.
This extension:
- ✅ Works completely offline
- ✅ Never sends data to any server
- ✅ Requires no special permissions
- ✅ Only stores your theme preference (dark/light mode)
- Chrome 88+ (Manifest V3)
- Edge 88+
- Brave 1.20+
- Opera 74+
If this extension helped you, consider buying me a coffee! ☕
MIT License - feel free to use and modify as needed.
- Initial release
- JSON formatting with configurable indent
- Interactive tree view
- CSV export for flat arrays
- Dark/light mode support
- Keyboard shortcuts