JSON Formatter
Format, validate, and explore JSON with Monaco Editor, interactive tree view, and JSON Path filtering — all in your browser.
Enter your text
Paste or type your content into the input field.
Adjust settings
Configure options to get the result you want.
Copy or save
Copy the output to clipboard or save it.
Key Features
Monaco Editor — Code Like in VS Code
Full-featured code editor with syntax highlighting, bracket matching, code folding, and auto-completion. The same editor that powers VS Code.
Interactive Tree View Explorer
Navigate complex JSON structures visually. Expand, collapse, and inspect nested objects and arrays with item counts at every level.
Real-Time Validation as You Type
Instant syntax checking with live Valid/Invalid status indicator. Catch errors before they reach production.
JSON Path Filtering
Query specific values using JSON Path expressions like $.address.city or $.items[0]. Drill into deeply nested data instantly.
Resizable Split Pane Layout
Drag the divider to customize editor and viewer proportions. Double-click to reset to 50/50. Adapts to mobile with stacked layout.
100% Private — Zero Server Uploads
All processing happens in your browser. Your JSON data never leaves your device — safe for API keys, tokens, and sensitive configs.
About This Tool
Professional JSON Formatter & Viewer
JSON Formatter is a free, professional-grade JSON tool that combines a Monaco code editor, interactive tree view, and real-time validation in one interface. Paste messy or minified JSON and instantly get clean, human-readable output with syntax highlighting, code folding, and visual tree exploration.
Whether you're debugging API responses, inspecting deeply nested data structures, reviewing configuration files, or preparing data for documentation — this tool gives you everything you need without leaving your browser or uploading a single byte.
Common Use Cases
- API Development & Debugging: Paste raw API responses, format them instantly, and use the tree view to navigate deeply nested objects
- Configuration Files: Clean up
package.json,tsconfig.json,.eslintrc, or Kubernetes manifests - Data Exploration: Use JSON Path to filter large datasets and find specific values without scrolling through thousands of lines
- Code Reviews: Compare JSON structures visually with the tree view to spot differences quickly
- Documentation: Format and export well-structured JSON examples for technical docs and tutorials
- Database Records: Inspect and format JSON stored in MongoDB, CouchDB, or PostgreSQL JSONB columns
Privacy-First JSON Processing
Your JSON data is processed entirely in your browser using native JavaScript parsing and the Monaco Editor engine. No data is transmitted to any server — ever.
- Your data never leaves your device — zero network requests during processing
- Safe for sensitive API keys, authentication tokens, and configuration secrets
- Works completely offline after the page loads — no internet required
- No analytics on your JSON content — we track tool usage, never your data