A builder's playground
Free browser-based developer tools that respect your privacy. No ads, no tracking, no data leaves your browser.
100% client-side
Everything runs in your browser. Nothing is uploaded.
No tracking
No ads, no analytics cookies, no data collection.
Free & open
Use as much as you want, no sign-up required.
Tools
View all →JSON
Formatter
Pretty-print with configurable indentation.
Validator
Validate with detailed line & column errors.
Minifier
Compress by removing all whitespace.
Diff
Compare two documents side by side.
To TypeScript
Generate TypeScript interfaces from JSON.
Repair
Auto-fix broken JSON with common errors.
Tree Viewer
Explore in an interactive, collapsible tree.
Sort Keys
Sort object keys alphabetically.